Keto Lemon Bars {6 Ingredients}

This keto lemon bar recipe features a buttery shortbread crust atop a creamy, zesty lemon filling. They’re wildly refreshing and only 2 grams of net carbs per bar!

Want more lemony keto desserts? Try my keto lemon meringue pie, keto lemon curd, and keto lemon blueberry muffins next.

This may be controversial, but I often prefer lemon desserts over chocolate ones. When I’m watching my carbs, that means I make my low-carb lemon bars by the dozen. 

The tangy, gooey lemon filling is complemented by the crisp shortbread crust, making for a balance of flavors and textures that rivals my traditional healthy lemon bars!

Why I love this recipe

• They’re easy to make. Even if you’ve never made a lemon bar a day in your life, I promise you’ll have no trouble making these. 
• Bursting with lemon flavor. This is for all you lemon lovers out there, especially those of us watching our carbs. 
• 2 grams of net carbs. Oh, and they also happen to be gluten-free.
• Uses fresh OR bottled lemon juice. I prefer fresh juice, but when I don’t have any on hand, the bottled stuff works just as well.

★★★★★ REVIEW 

“These are the best low-carb lemon bars I’ve ever made!” – Ellen

Ingredients needed

• Almond flour. This is used for the shortbread crust. Be sure to use blanched almond flour, not almond meal.
• Butter. I prefer unsalted butter since it doesn’t disrupt the flavor of the other ingredients. 
• Sugar-free powdered sugar. Either use the store-bought stuff or make your own homemade powdered sweetener with allulose or monk fruit sweetener. 
• Lemon juice. For the lemon flavor! Use either fresh lemon juice or bottled lemon juice. 
• Eggs AND one egg yolk. Use room temperature eggs, plus an extra egg yolk to give the filling a gooey texture and gorgeous yellow color. 
• Coconut flour. Thickens the filling.

How to make keto lemon bars

I’ve included step-by-step photos below to make this recipe easy to follow at home. For the full printable recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.

Step 1- Prep. Preheat the oven to 180C/350F and line an 8×8-inch baking dish with parchment paper.

Step 2- Make the crust. In a large mixing bowl, combine the almond flour, melted butter, and powdered sugar. Transfer the mixture to the lined pan and press into place.

Step 3- Bake. Bake the crust for 15 minutes or until golden.

Step 4- Make the filling. In a separate bowl, whisk together the softened butter, lemon juice, and powdered sugar. Once glossy and smooth, add the eggs and egg yolk. Mix well, then add the coconut flour. 

Step 5- Second bake. As soon as the crust is done baking, remove it from the oven and spread the filling on top. Bake the bars for 20-22 minutes or until the center is firm but jiggles slightly. 

Step 6- Cool and serve. Remove from the oven and let cool in the pan. Refrigerate for 2 hours. Once ready to serve, sprinkle with extra powdered sugar.

Arman’s recipe tips

• Keep an eye on the crust. You’ll add the lemon filling the second it’s done baking. This makes sure the filing remains thick and that the eggs don’t separate. 
• Don’t overbake the bars. They’ll continue to cook as they cool down and thicken more after they’ve been refrigerated. 
• Add more lemon flavor. If you’re like me and prefer your lemon bars extra tart, add some lemon zest to the filling. 
• Enhance the flavor of these sugar-free lemon bars by adding a pinch of salt or one teaspoon of vanilla extract.

Storage instructions

To store: Leftover bars should be stored in an airtight container in the refrigerator for up to two weeks. 

To freeze: Place bars in a ziplock bag and store in the freezer for up to 6 months. Thaw in the refrigerator overnight. 

More keto dessert recipes you’ll love

Originally published August 2020, updated and republished June 2024