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
Mark says
Carolyn
Can’t wait to make this. Can you use powdered erithytol in this crust or does it have to be granular?
Thank you!
Cathy Forehand says
i am wanting to switch to a different brand of powdered erythritol. i can only find granular. do you know if anyone besides Swerve makes a powdered erythritol? Thank you.
Cathy Forehand says
Carolyn do you know of a *powdered* pure erythritol? i want to switch from Swerve. Thank you.
Charles Perryman says
Dear Carolyn,
My request to you does not regard the current subject, but I must contact you to share my Special Request!! I have been following you for several years and I have built a huge library of your many works. I am almost 84 years old and I am not baking a great deal anymore. I have researched my material and thought I had included your recipe for Keto Carrot Cake; but I can not find it. I have been sharing my Love for You and Your Wonderful Career with a Dear Friend. I wanted her to bake your Keto Carrot Cake for me. I know I am fighting Dementia, but am I wrong; I just knew you must have developed this Wonderful Recipe!! With Warm Regards, Charles…PS You are my Most Favorite Food Blogger, Ever!!
Mary Wright says
OK, the topping was really thin and I was concerned because I poured it onto the crust, rather than spreading it. Baked just a couple minutes longer than recipe and the top seemed fluffy and soft out of the oven. Let cool, then put the dish in the freezer for 15-20 minutes to cool more. Nice creamy texture now and good flavor. Crust is a little softer than expected, but tastes good.
Norma says
Is the quantity of cream cheese right?
Carolyn says
Yes… it’s meant to add structure and texture without making them into cheesecake.