These sugar free Key Lime Pie Bars feature a tangy citrus filling and a tender almond flour shortbread crust. They are a popular summertime keto dessert with good reason!
I consider these key lime pie bars as proof that the keto diet is not one of deprivation. Really, people, when you are able to eat something this tangy, this flavorful, this creamy, life is good.
I’ve been doing this for quite some time now and it can still take even me by surprise. Aren’t we the lucky ones, to have discovered this little secret?
Key lime was one of my dad’s favorite flavors, so I always think of him when I make anything with it. I have a classic Keto Key Lime Pie that I know he would have loved. And I am quite certain he would have gobbled down these delicious bars with gusto!
Why you will love these bars
This citrusy keto dessert is somewhere between cheesecake and pie, but easier to make than either of them.
I use the classic technique of mixing egg yolks with sugar free condensed milk. But the added cream cheese allows the filling to set more easily. It’s also a little creamier and has greater volume this way.
The shortbread crust complements the tangy filling perfectly. It’s much the same as my easy keto pie crust, but baked in a square metal pan.
These bars are easy to make, but they do require some chill time to set properly, so have a little patience. Then you have a dessert that has only 2.4g net carbs per serving. You could even afford to eat two of them!
Reader Reviews
“This is so delicious and easy to make. The hard part is sticking to only eating a single serving. Thank you for your wonderful cookbooks and recipes with easy to follow instructions and tips (yep, I read the whole post not just jump to the recipe).” — Cara
“Just thought you ought to know that I used this recipe in a workplace cooking competition where it competed against some very non-keto desserts. I am pleased to say it was declared the winner by a mile! Thank you for creating these delicious recipes that make keto dieting so much easier!” — Gabrielle
“Carolyn, these are wonderful. I made them yesterday, tried them today, and my husband and I both enjoyed them. I used regular limes because that’s what I had. I wasn’t sure about keto baking after the last recipe I made (not from your blog), but now I understand that I have to choose recipes from the right blog… 🙂” — Susan
Ingredients you need
- Almond flour: Coconut flour does not make a very good crust, which is why I prefer to use almond flour. Pecan flour would also be delicious and for a nut-free option, you can use sunflower seed flour.
- Sweeteners: Keep in mind that only erythritol-based sweeteners such as Swerve will produce a crisp crust. And using some BochaSweet or allulose in the condensed milk helps keep it creamy and soft. See the Expert Tips for more sweetener options.
- Condensed milk: You can’t purchase sugar free condensed milk, you need to make it yourself. It’s easy and worth it! Do this first, so you can let it cool before making the filling.
- Cream cheese: I use cream cheese to help thicken the filling and give it a little more substance. It makes it extra creamy, too!
- Key Limes: Key limes are teeny tiny things and it takes quite a few of them to get enough juice. They are a pain to squeeze! So I recommend the bottled juice from concentrate. I found some at the grocery store but it’s also available on Amazon.
- Eggs: You only need the yolks for the custard base of these bars. Don’t waste those egg whites. Use them to make some keto meringues!
- Kitchen staples: Butter and salt.
Step-by-step directions
- Make the condensed milk: Follow the instructions for my easy keto condensed milk and let it cool completely.
- Prepare the crust: In a medium bowl, whisk together the almond flour, sweetener, and salt. Stir in the melted butter until the mixture begins to come together.
- Bake the crust: Transfer mixture into an 8×8 baking pan and press firmly into the bottom. Bake 12 to 15 minutes at 325ºF, until just golden brown around the edges.
- Prepare the filling: In a large bowl, beat the cream cheese and lime zest until smooth. Beat in the egg yolks until well combined. Slowly beat in the condensed milk and lime juice until the mixture is smooth.
- Bake the filling: Spread the filling over the crust and bake 18 to 20 minutes, watching carefully to make sure it doesn’t brown at all. Remove and let cool, then refrigerate at least one hour to firm up.
- Garnish: Top with lightly sweetened whipped cream and lime slices
Expert tips
I found I didn’t need to add any other sweetener to the filling besides the condensed milk. However, if you like things sweeter and less tangy, then feel free to add a tablespoon or two of powdered Swerve or some stevia extract.
Make sure the egg yolks are at room temperature before adding them to the cream cheese. Cold eggs or yolks will make it clump up again and you won’t have a smooth filling.
If you don’t care about authenticity, feel free to use regular Persian limes. The bars will still be delicious!
Sweetener Notes
The only sweetener that will produce a crisp crust is erythritol. Any amount of allulose or BochaSweet will make it much softer so keep that in mind. If you don’t care about crispness, feel free to use your favorite. Allulose will make it brown faster.
The filling really requires some BochaSweet or allulose (in the condensed milk) to have a good, soft consistency. If you use only erythritol based sweeteners, the filling will likely recrystallize as it cools. You can play with the amounts, adding more of the allulose or BochaSweet if you prefer. But it may take longer to set if it contains more allulose.
Frequently asked questions
Although they are slightly sweeter and less tart than regular limes, key limes can be used in keto recipes. The juice has only about 3g of carbs per ounce (two tablespoons).
Because of the creamy filling, these bars should be refrigerated at all times. Store in a covered container and they last up to 5 days in the fridge. They can also be frozen for several months. I would leave off any whipped cream and garnish until you have thawed the bars.
This keto key lime pie bar recipe has 3.4g of carbs and 1g of fiber per serving. That comes to 2.4g net carbs per bar.
More healthy keto lime recipes
Cilantro Lime Cauliflower Rice
Cilantro Lime Cauliflower Rice takes only 5 simple ingredients and has spectacular flavor. This copycat of the famous Chipotle rice goes with all of your favorite healthy dinners.
Keto Key Lime Cheesecake
Keto Key Lime Cheesecake is a tangy sweet dessert recipe that serves just two people. This easy dessert recipe takes only 6 ingredients and 15 minutes to make!
Skinny Keto Margaritas
Look no further for the BEST keto margarita recipe! With 4 simple ingredients, these easy sugar-free cocktails have that classic margarita flavor without the extra carbs.
Key Lime Pie Bars Recipe
Ingredients
Shortbread Crust:
- 1 ¼ cups almond flour
- ⅓ cup Swerve Sweetener (old formula)
- ¼ teaspoon salt
- ¼ cup butter melted
Key Lime Filling:
- 3 ounces cream cheese softened
- 2 teaspoon lime zest
- 4 large egg yolks room temperature
- 1 cup sugar-free condensed milk
- 6 tablespoon key lime juice
Instructions
Shortbread Crust:
- Preheat the oven to 325ºF.
- In a medium bowl, whisk together the almond flour, sweetener, and salt. Stir in the melted butter until the mixture begins to come together.
- Turn out the mixture into an 8×8 baking pan and press firmly into the bottom. Bake 12 to 15 minutes, until just golden brown around the edges.
- Remove and let cool while preparing the filling.
Key Lime Filling:
- In a large bowl, beat the cream cheese and lime zest until smooth. Beat in the egg yolks until well combined. Slowly beat in the condensed milk and lime juice until the mixture is smooth.
- Spread the filling over the crust and bake 18 to 20 minutes, watching carefully to make sure it doesn’t brown at all. Remove and let cool, then refrigerate at least one hour to firm up.
- Top with lightly sweetened whipped cream and lime slices
Judy says
Amazing birthday dessert for my significant other! Question for you, many recipes either use cream cheese or sour cream. What’s your take on using sour cream in lieu of cream cheese? My Original batch was made using your original recipe but with his birthday coming up, I wanted to make it where it had more of a key lime taste (based on his feedback) and wanted to ask about sour cream. Thank you!
Debbie Kuriger says
WOW!! These are amazing!!! Thank you so much!! I’m thinking I can do some lemon bars, too!! I’m going to start “following” you on Pinterest after this one!! Yummy!!
Robin says
How many bars does this recipe make? Making it today for my son and daughter in law. They make a really great key lime pie. Darn Floridians..lol. Hopefully they will love this keto version.
Carolyn says
Hi there. The number of servings is always listed at the top of the recipe. In this case, it’s 16.
Marcella Varga says
I made these and they were a smash hit!! I was wondering how the filling could be modified for a Cheesecake filling??
Carolyn says
Sure but you’d probably need to double it.
VAnessa says
Thanks for sharing! Do they keep long?
Suzanne says
These look so good! It looks like they could be make into lemon bars easily too!
Beth R. says
Made these for our Superbowl gathering and they are delicious! I will say I wasn’t sure about the sugar-free condensed milk. I think I added too much xantham gum – it was basically glue-like the next day in the fridge. But it worked. These are tart and the crust is heavenly! I will sprinkle the top next time with a bit of swerve confectioners like you do with lemon bars! A must make for keto (and non) looking for a refreshing dessert!
Keto Katie says
WOWZA! This is the Unicorn of all Keto dessert recipes (and believe me, I’ve tried TONS!) – made them for our FL relatives and ZERO out of NINE people suspected they were keto or low carb at all! These are decadent and so insanely delicious — I now make a double batch and freeze them (with the SF whipped topping on!) so I can have one whenever. Finally, a keto dessert recipe that tastes exactly identical to the real deal. Thank you!!
Carolyn says
That’s so fabulous to hear!
Michael Helm says
I made this spur-of-the-moment NY eve. I make a regular KLP using something close to the Nellie & Joe simple pie recipe, & the result is pretty popular – but way too much sugar content. I’ve tried a number of keto recipes & this one looks promising (others have coconut or avocado fat in them). For this pie to work in our group, it seems like the texture and the consistency are important.
This recipe’s result pie had good reaction about flavor. The consistency was more like cheesecake (from the cream cheese perhaps?). It also was a bit heavier, and definitely crumbled more – wouldn’t stay together nearly as well as my regular KLP. I also pick up a bit of graininess altho no one complained. I had Lekanto Monkfruit Golden in house, didn’t have time to get Swerve. I tried to powder it in a blender before adding to the milk. BTW the recipe amounts were maybe just a little more than needed for the pie – I had a small amount of overflow (which is ok).
It was tricky for me to tell when it was done – the regular recipe has a light, nearly dry look at about 15min – this pie still had the “sweaty” look at 20, & I kept baking it for at least another 5 mins – I think that was a mistake, the crust was way too done. The regular KLP rises slightly, this recipe looks like it does when cooking but then condenses.
Thanks for reading this far – any recs? I’m thinking for the next refinement I’d use Swerve and/or leave out the cream cheese for now. (I like the idea of a KL cheese cake but I want to get something close to the popular regular pie.) Any hints on cooking time? Better cooler and longer or hotter & quicker? My oven is not real accurate for temperatures but is consistent.
Carolyn says
I honestly think you need to make peace with the fact that this will never be the high carb version of Key Lime Pie. It’s not meant to be. Also, this isn’t meant to be baked in a pie so that could be a large part of the problem, since it would bake very differently and yes, it wouldn’t hold together nearly as well. Another issue is the fact that you didn’t use a powdered sweetener, which accounts for the graininess.
Kathleen Lesnau says
Suggestions for the left over egg whites? Another recipe perhaps?
Carolyn says
https://asweetlife.org/21-low-carb-recipes-for-leftover-egg-whites/
Linda says
These are AMAZING – a friend whose favorite dessert is key lime pie and who is not keto/low carb crowned these the best dessert EVER!
I increased the filling by 1.5 since the condensed milk recipe makes 1.5 cups – didn’t want the rest to go to waste. I also toasted the almond flour before pressing in to the crust and used browned the butter – just to give it a little more nuttiness to get it closer to a graham cracker kinda taste.
Thanks for another amazing recipe, Carolyn. You are a rockstar!
Denise says
Well these are fantastic and a hit with everyone whether or not they eat keto! My first batch had a hint of bitterness. Turns out, I put pith in instead of zest. I did not know that “zest” is “peel.” I fixed it with the second batch and they were perfect. So freaking delicious. Thank god the condensed milk is gone so I can’t make any more of these little temptations. I had some problems making the SCM. The first batch didn’t reduce at all, so I cooked it longer and ended up with very caramel-flavored SCM. I tried again and stopped at thirty minutes even though it hadn’t reduced at all. Didn’t thicken like it should have. The first batch was a perfect consistency. So, I mixed them together and that seemed to do the trick! I even used the caramel heavy one on its own this last batch and the flavor was fine. Thanks for a great summer recipe! Do you have one like this for chocolate cream pie?
Carolyn says
Oh, I am sorry about that. Yes, the pith tends to be much more bitter.
Denise rodriguez says
I learned the hard way. The second batch was PERFECTION! And, I have since figured out that the crust makes a really great cookie for using cookie cutters. The dough is a bit delicate before baked so I used a spatula to move each unicorn cookie to the baking sheet, but once they cool, they are just perfect for a glaze of being sprinkled with “sugar.” You’ve given me a great start to having a great variety of keto cookies for my Christmas baking extravaganza. Do you have a chocolate cream pie recipe?
Lori says
Can I use coconut flour instead of almond flour? I have almond meal but not almosnd flour.
Carolyn says
Use the almond meal. Coconut flour does not make a very good crust.
Byenia says
Made this last night for the first time and we enjoyed it. This is the 3rd or 4th recipe I’ve tried from you and all have been wonderful. 🙂
Ira says
These are amazing! Tastes just like the real thing! I used 1/2 cup of butter in the crust and added a dash of cinnamon. I doubled the filling recipe and baked it in a cake pan for 5 extra minutes. Only used half the condensed milk in the filling and saved the other half to pour on top after baking, instead of adding whipped cream. They were a hit with the whole family!
Lyle Drew says
Please correct spelling of “lime” (not line) in my last post. Thanks.
Lyle Drew says
Great recipe. I doubled the filling amount but used half line and half lemon juice (same total amout as per the recipe) but kept a single recipe amount of shortbread crust when spread over a 9×18 baking pan. The end result was a nice mix that wasn’t overpowering with a thinner crust which I prefer. The only problem is that it doesn’t last very long before its all gone.????
Erin | Dinners,Dishes and Dessert says
This looks incredibly delicious! I’m going to have to try this.
Kristyn says
I am usually a chocolate fan, but these were incredible! Refreshing & so tasty! My family will love them!
Jessica says
Yum! These were such a yummy guilt free treat! Thank you!