Keto Lemon Bars

5 from 1 vote

Aug 01, 2019, Updated Feb 22, 2024

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Keto Lemon Bars – low-carb, sugar and gluten-free alternative of a very popular dessert. Thick and buttery crust with a tangy and sweet, delicate lemon layer on top. Very quick and easy to make with a few Keto pantry staples.

If you have been following me for a while, you may know that I love lemon and citrus desserts. After sharing this Keto Lemon Tart recipe, I’ve been wanting to make some low-carb lemon bars.

There turned out to be and easy fix. I adapted the recipe from my Classic Lemon Bars With Shortbread Crust.

The base in this low-carb lemon squares recipe is made with just almond flour, melted butter, sweetener and vanilla (optional).

Almond flour produces a thick and dense buttery crust, which can easily hold the filling. I did not use any coconut flour in this recipe.

The filling is made with freshly squeezed lemons (unlike lemon jell-o, that some recipes call for), sweetener and eggs. The filling does need a thickening agent, this is why I used almond flour, Xantan gum and even some cornstarch (the amount used is totally fine for the Keto diet) to thicken the filling.

The result – sweet, tangy, buttery and soft Keto Lemon Bars.

Are lemons on on Keto?

Yes, lemons are totally fine on the Keto and any low-carb diet. Lemons are responsible maintaining the normal pH balance of the body, because of their alkaline components.

Keto lemon bars cut on a piece of parchment paper

They are great to add to water, use in dressings, salads, marinades and desserts like these sugar-free lemon squares.

One whole lemon has 5.5 grams of total carbs and the juice of one medium lemon is 3.3 grams of total carbs.

Keto lemon bar with a bite taken into it

What ingredients do I need to make this Keto Lemon Bars Recipe?

butter
almond flour
sweetener (see notes on what sweetener to use)
vanilla extract
lemon zest
lemon juice
eggs
Xantan Gum
cornstarch (optional)
topping (strawberries, blueberries, lemon slices -all optional)

Please, if you are not a fan of tangy desserts, make sure you increase the amount of sweetener in the filling with 1-2 tablespoons or use 5-8 drops of liquid stevia for extra sweetness.

Keto lemon bars with slices of lemon on top

What low-carb sweetener is best to use in this Keto lemon bars recipe?

I used Swerve confectioners in both the crust and the filling. When I make lemon desserts and use regular granulated erythritol, it tends to crystalize, once the product is baked (happens a lot with custards).

This is why for these lemon bars I prefer using either confectioners erythritol or Swerve Confectioners. Swerve is basically erythritol with added oligosaccharides. The addition of these helps make Swerve the same level of sweetness as white sugar, whereas erythritol is only about 70% as sweet as sugar.

So if you use erythritol, you may want to increase the amount of sweetener on both the crust and filling with 1/3.

How to make Low-Carb Lemon bars?

For the filling: (Make it first)
Beat egg in a bowl. Add sweetener, cornstarch (optional), Xantan gum, lemon juice, lemon juice, lemon zest and almond flour. Beat to combine.
Preheat oven to 350 F.
Line a 8×8 baking dish with parchment paper.
For the crust:
In a bowl combine the almond flour, sweetener, butter and vanilla, stir to combine.
spread the crust dough covering the bottom of the baking dish.
Bake for 15 minutes.
Pour the filling on top and bake for 25-30 more minutes, until the top is set.
Cool completely, then refrigerate for 1 hour.
Cut into 16 squares. Serve.
To store, wrap in plastic wrap and refrigerate for up to 1 week.