Keto Lemon Bars

This keto lemon bar recipe features a foolproof 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!

Table of Contents

1. Why I love this recipe
2. Ingredients needed
3. How to make keto lemon bars
4. Arman’s recipe tips
5. Storage instructions
6. More keto dessert recipes you’ll love
7. Keto Lemon Bars (Recipe Card)

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.

Ingredients needed

Here’s what you’ll need for the crust:

• Almond flour. This is used for the shortbread crust. Be sure to use blanched almond flour, not almond meal.
• Allulose. My preferred keto sweetener that dissolves just like sugar does. I’d recommend avoiding monk fruit sweetener as it can be grainy.
• Egg. Room temperature.

For the filling:

• Lemon juice AND zest. For the lemon flavor! I suggest using fresh lemon juice as we’ll also be using the zest.
• Egg. Again, use room temperature eggs. 6 eggs might seem like a lot, but trust me, it yields the most gooey filling ever.
• Allulose. For sweetness. Again, please do not use monk fruit sweetener or other keto sweeteners that don’t dissolve like sugar does.

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, allulose, and egg and mix well. 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. Whisk the eggs together until no whites remain. Add the sugar, lemon juice, and lemon zest and continue whisking until smooth.

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

• Keto fudge
• Keto chocolate chip cookies
• Keto peanut butter bars
• Keto pound cake

Originally published August 2020, updated and republished June 2024