These delicious and easy to make keto lemon bars are the perfect low-carb treat. An almond flour shortbread crust is topped with lemon curd for a tasty dessert for lemon lovers.
If you love sugar free lemon curd, you will enjoy these keto lemon squares as the topping is pure lemon joy. It's not too tart or sweet either. Once chilled overnight, these low carb and gluten-free lemon bars are full of they zesty goodness of the traditional lemon bars but without the sugar and carbs.
Before baking these we had not really experienced lemon bars as they are an American dessert and not widely available in the UK. After tasting them, we were in love and feel short changed in our childhood desserts! These should be a weekly treat.
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Can you have lemons on keto diet?
While lemons do contain some natural sugars, they are relatively low in net carbohydrates. The approximate carbohydrate content in 1 fluid ounce (about 30 milliliters) of lemon juice is around 1.5 grams. In recipes like keto lemon bars, the amount of lemon used is typically small enough that it fits within the macros of a ketogenic diet.
The net carbs in these keto lemon bars are just 4g per square. A traditional lemon bar can have up to 20 grams carbs.
With a few simple keto ingredients, you can make refreshing low carb lemon bars for summer. Or any time of the year when you want a lemon dessert too!
- Almond flour - use finely ground almond flour.
- Lemon juice - freshly squeezed is recommended rather than anything out of a bottle.
- Lemon zest - use unwaxed lemons and wash them before zesting.
- Sweetener - for the low carb sweetener we used allulose but any other sweetener such as monk fruit sweetener or swerve can be used.
- Xanthan Gum - this helps create the right texture for the lemon bars without needing to use traditional thickeners like cornstarch or flour.
- Eggs - Use room temperature eggs.
How to make keto lemon bars.
This is an easy recipe to make but needs to be made the day before you want to eat them. Make the lemon filling whilst the base is cooking.
Mix the base ingredients together.
Form into a dough.
Press into a 8 inch square tin.
Bake for 10 minutes until golden.
Whisk the lemon juice, zest, sweetener and eggs.
Add the almond flour and xanthan gum.
Pour on top of the base and bake.
Once chilled, cut into squares.
Keto Lemon Bar Recipe Tips
Unflavored gelatin can also be used as a substitute for xanthan gum. Both ground chia seeds and ground flaxseeds can work as substitutes for xanthan gum. They provide similar binding properties and add a bit of texture to the recipe. Use them in a 1:1 ratio as a replacement for xanthan gum.
Be careful not to overbake your lemon bars, as this can cause them to become dry and crumbly. The filling should be just set and slightly jiggly in the center when you remove them from the oven.
Before serving, dust the tops of your lemon bars with allulose or a mixture of powdered sweetener and lemon zest for a finishing touch.
Store leftover keto lemon bars in an airtight container in the refrigerator for up to 5 days. They can also be frozen for longer storage.
Before freezing, ensure that your keto lemon bars have cooled completely to room temperature. Cut the lemon bars into individual portions or into the desired size for serving. This makes it easier to thaw and enjoy only what you need at a time.
If you prefer, you can wrap each individual portion of lemon bars in plastic wrap or parchment paper before placing them in an airtight container or freezer bag. This can help prevent them from sticking together during freezing.
Place the wrapped or unwrapped lemon bars in an airtight container or freezer bag. Make sure to remove as much air as possible from the container or bag to prevent freezer burn. Place the container or bag of lemon bars in the freezer. Store them in a flat position to prevent them from becoming misshapen.
Thawing and serving
When you're ready to enjoy the frozen keto lemon bars, remove the desired number of portions from the freezer and let them thaw in the refrigerator overnight. Alternatively, you can thaw them at room temperature for a few hours before serving.
Once thawed, your keto lemon bars should be just as delicious as when they were freshly made. Serve and enjoy!
Keto Lemon Bars
Make the base
- Pre-heat the oven to 180C/350F degrees and line a 8 inch square baking tin with parchment paper.
- In a large bowl mix the dry ingredients, then add the melted butter into a dough. The mixture will be a bit sticky.
- Press the dough into the lined baking tin and spread evenly.
- Bake for 10 minutes until golden.
- Remove from the oven and pour the filling on top of the base.
Make the Filling
- Make the filling whilst the base is cooking or before the base is made as it needs to be poured onto the base once it is cooked.
- In a large mixing bowl, add the eggs, egg yolk, lemon juice, lemon zest and sweetener. Whisk until smooth.
- Stir in the almond flour and xanthan gum.
- Pour on top of the cooked base and bake for 15-18 minutes until the middle is slightly jiggly.
- Turn off the oven, open the oven door a jar and allow to cool for 1 hour.
- Remove the baking tin from the oven and place in the fridge to cool for at least 4 hours. Ideally over night.
- Cut into square and remove from the tin. Sprinkle with powdered sweetener on top (optional).
The information shown is an estimate provided by an online nutrition calculator.