4.91 from 81 votes

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Keto Lemon Sour Cream Pie

Name: Keto Lemon Pie Recipe
Prep time: 20 min
Cook time: 10 min
Total time: 270 min
Ingredients: 6 tbsp powdered sweetener; 2 to 4 tbsp allulose (or xylitol); 1/2 tsp glucomannan ((can sub xanthan gum, see notes)); 3/4 cup heavy cream; 1 tbsp lemon zest; 1/2 cup freshly squeezed lemon juice; 4 large egg yolks; 3 tbsp butter (chilled and cut into pieces); 3/4 tsp lemon extract; 1 cup full fat sour cream; 1 keto pie crust (fully baked)

ByCarolyn Ketchum Updated onMay 4, 2025

276 Comments

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This Keto Lemon Pie has a tangy sour cream filling and an easy press-in crust. It's low carb, sugar-free, and utterly craveable.

Recipe Print

Keto Lemon Pie in a a white pie plate on a white wooden table.

One bite of this Keto Lemon Cream Pie and you will be hooked! It has a mouthwateringly tangy, creamy filling in a crisp keto pie crust. Honestly, it’s like sunshine on your tongue! It really doesn’t get any better than this.

A slice of keto lemon cream pie on a white plate with three raspberries.

There are some desserts that just stick with you. And I don’t mean this in a bad way, as in something making you too full or uncomfortable. I mean it in the sense that it was so delicious, you can’t stop thinking about it. This lemon sour cream pie is one of them.

I have a lot of great keto pie recipes, like Keto Pecan Pie and Keto Peanut Butter Pie. But if you love lemon, then this keto dessert is an absolute must. It’s been a fan favorite since I first published it in 2016.

And now I’ve tweaked the recipe just a smidge to make it better than ever!

Keto Lemon Sour Cream Pie in a white pie plate, with several slices cut out of it.

Why we love this recipe

Gluten-free crust: My famous almond flour pie crust is super easy and completely gluten-free and low carb.
Smooth custard filling: The pie filling involves making a lemon custard and then folding in some sour cream. It is so velvety smooth and rich!
Tangy lemon flavor: Pucker up, buttercup! This wonderful lemon cream pie is full of that bright, fresh citrus flavor.
Low carb dessert: With only 5.7 grams of carbs per serving, it’s a perfect dessert for low carb and keto diets.

Reader’s Thoughts

“Made this yesterday for the first time. It was truly delicious! Served it to my non-keto friends and family and they all love it. Carolyn, you are a keto baking genius!! Thank you for working out this recipe and for sharing this and all your other great recipes.” — MjeanF

Share Your Thoughts!

Ingredient Notes

Sweetener: I used a combination of Swerve confectioners and some allulose to get an extra smooth, creamy filling. I also like this pie quite tangy so I only used half a cup sweetener total.
Glucomannan: Conventional sour cream pie uses cornstarch to thicken the filling, but glucomannan helps the keto filling set properly. You can also use xanthan gum.
Heavy cream: Heavy cream gives the pie a silky consistency.
Egg yolks: You also need plenty of egg yolks for a custard filling like this one.
Lemon: You can’t have lemon pie without the lemon!
Butter: Chilled butter helps cool the custard more quickly and helps it set faster.
Lemon extract: For more lemon flavor, I also use a little lemon extract.
Sour cream: Use full fat sour cream as it may not set properly with anything less. I don’t recommend substituting greek yogurt for this recipe.
Easy keto pie crust: You will want to make the fully baked version of this crust. For a nut free option you can use sunflower seed flour for the crust. It is a 1:1 ratio with almond flour, but do know that your crust will be more gray in appearance.

Step by step directions

A collage of 6 images showing how to make Keto Lemon Sour Cream Pie.

Whisk the sweeteners: In a large, heavy-duty saucepan, whisk together the sweeteners and glucomannan.
Simmer the cream: Add the cream, egg yolks, lemon zest, and lemon juice and whisk to combined. Set over medium heat, whisking frequently, until the mixture begins to thicken. This takes 7 to 10 minutes. Keep a close eye on it, you do not want it to curdle.
Add the butter: Remove the pan from the heat and whisk in the butter and lemon extract. Let cool to room temperature.
Add the sour cream: Whisk in the sour cream until no lumps remain. Pour the mixture into pie shell and refrigerate for at least 4 hours to set – the longer, the better, so overnight is best if you can wait that long.
Serve: Top with lightly sweetened whipped cream and serve.

A slice of lemon cream pie on a metal cake lifter, being lifted away from the rest of the pie in a white pie plate.

Tips for Success

For this recipe, you need a fully-baked pie crust. So bake it 15 to 20 minutes, until it’s a nice light golden brown. Let it cool completely.

As with any custard-like filling, you need to watch this one carefully. Don’t walk away while it’s cooking. Just hang out there right by your stove, whisking and watching, as it will likely take less than 10 minutes.

The best way I can describe knowing when it’s done is watching your whisk carefully as you move it through the custard. When it’s first cooking, it is very liquid and sloshes around the pan. When it starts to thicken, you will see the mixture move more lazily. Your whisk will almost leave tracks for a quick second. Once it hits that point, remove it from heat immediately.

Troubleshooting:
– Oh no, you over-cooked the custard and you see curdles! Quick, get it into a blender (or use an immersion blender) and blend on low until smooth.
– Oh no, you undercooked the custard and the pie didn’t set properly! Simply stick it in the freezer and serve it frozen. It will be delicious!

Top down image of two slices of lemon cream pie on white plates, with a teal patterned napkin.

Sweetener options

The pie crust requires an erythritol based sweetener to crisp up properly. Any amount of allulose will make it quite soft.

For the filling, I recommend a mix of erythritol and allulose (or xylitol). This helps provide enough structure but also keeps the filling from re-crystallizing as it cools. I don’t recommend using only allulose, as it may never firm up properly. If you use only erythritol, I recommend using a powdered version and only whisking it at the end of cooking the custard.

If that sounds confusing, please leave a comment and I will explain further what I mean.

Frequently Asked Questions

Can I make this Keto Lemon Cream Pie in advance?

I recommend making this pie one day in advance of serving, as it firms up better overnight. I don’t suggest making it ahead much more than that, unless you plan to freeze it. Creamy custard desserts like this should be served and consumed within 4 to 5 days.

How do you store keto lemon cream pie?

Store the pie in the fridge at all times. It will last for up to 4 days. You can also freeze this pie for up to a month. Wrap it up tightly to avoid freezer burn and only add the whipped cream when ready to serve.

How many carbs are in a Keto Lemon Pie?

This keto lemon pie recipe has 5.7g of carbs and 1.8g of fiber per serving. That comes to 3.9g net carbs per serving.

A slice of Keto Lemon Sour Cream Pie on a white plate with several forkfuls taken it of it.

More Keto Lemon Desserts

4.91 from 81 votes

Keto Lemon Pie Recipe

Servings: servings

Prep Time 20

Cook Time 10

Total Time 4 30

This Keto Lemon Pie has a tangy sour cream filling and an easy press-in crust. It's low carb, sugar-free, and utterly craveable.

Ingredients

6 tbsp (91 g) powdered sweetener
2 to 4 tbsp allulose, or xylitol
1/2 tsp (0.25 tsp) glucomannan, (can sub xanthan gum, see notes)
3/4 cup (177.44 ml) heavy cream
1 tbsp lemon zest
1/2 cup (118.29 ml) freshly squeezed lemon juice
4 large (4) egg yolks
3 tbsp (42.61 g) butter, chilled and cut into pieces
3/4 tsp (1 tsp) lemon extract
1 cup (230 g) full fat sour cream
1 keto pie crust, fully baked

Instructions

In a large, heavy-duty saucepan, whisk together the sweeteners and glucomannan.
Add the cream, egg yolks, lemon zest, and lemon juice and whisk to combined. Set over medium heat, whisking frequently, until the mixture begins to thicken. This takes 7 to 10 minutes. Keep a close eye on it, you do not want it to curdle.
Remove the pan from the heat and whisk in the butter and lemon extract. Let cool to room temperature.
Whisk in the sour cream until no lumps remain. Pour the mixture into pie shell and refrigerate for at least 4 hours to set – the longer, the better, so overnight is best if you can wait that long.
Top with lightly sweetened whipped cream.

Video

Notes

Storage Information: Store the pie in the fridge at all times. It will last for up to 4 days. You can also freeze this pie for up to a month. Wrap it up tightly to avoid freezer burn and only add the whipped cream when ready to serve.

Xanthan gum: You can use xanthan gum instead of glucomannan, but you will want to whisk it into the filling after you take it off heat and before you whisk in the butter and lemon extract in Step 3. Sprinkle it lightly over top of the custard and whisk vigorously as you do so, so that it doesn’t clump up.

Nutrition

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Categories:

Gluten Free, Low Carb, Pies & Tarts,

Nutritional Disclaimer

Please note that I am not a medical or nutritional professional. I am simply recounting and sharing my own experiences on this blog. Nothing I express here should be taken as medical advice and you should consult with your doctor before starting any diet or exercise program. I provide nutritional information for my recipes simply as a courtesy to my readers. It is calculated using MacGourmet software and I remove erythritol from the final carb count and net carb count, as it does not affect my own blood glucose levels. I do my best to be as accurate as possible but you should independently calculate nutritional information on your own before relying on them. I expressly disclaim any and all liability of any kind with respect to any act or omission wholly or in part in reliance on anything contained in this website.

Free Bonus: Secrets to Keto Baking!

Carolyn Ketchum

I’m Carolyn, cookbook author, photographer, and unrepentant sweet tooth, I am devoted to creating delicious and innovative low carb recipes that don’t sacrifice on flavor. Keto has never been more delicious!

4.91 from 81 votes (18 ratings without comment)