These keto lemon bars strike that perfect balance of bright, tangy lemon flavor and a smooth, creamy filling on top of a buttery shortbread crust. If you’ve been missing a truly good low carb lemon bar, this one delivers.
They’re not quite a “dump and stir” recipe—but don’t let that scare you. The extra step is what gives these bars their rich, silky texture, and it’s absolutely doable (and worth it, I promise.)
If you don’t want to read the origin story of these keto lemon bars, please feel free to use the Jump to Recipe button on the top right of the page.
Lemon bars have always been one of my absolute favorite desserts. They are the thing I’m most likely to gaze longingly at through the glass at a bakery or coffee house – and sometimes I give in and have one.
I’m never really sorry until the next day when I wake up puffy and bloated from the gluten and sugar. Even then a perfect lemon bar is usually worth it if I’m being honest.
I finally decided though that it was high time I came up with a legit keto lemon bar recipe that would meet my low carb and gluten free criteria (and save me from the morning after bloating.)
As an added bonus these keto lemon bars are relatively simple to make, and just as good or better than the “real” thing. I’m not just saying that either, I tested these out on crowds of non low carbers at several parties – all with rave reviews and no leftovers.
This keto lemon bar recipe is basically the love child of my Lemon Almond Shortbread Cookies (crust), and my Sugar Free Lemon Curd (filling) recipes, with a few minor tweaks.
I like my keto lemon bars a little on the tart side, but you can increase the sugar free sweetener in the lemon curd if you prefer them sweeter – or you can add more powdered sugar free sweetener to the top of them after baking.
I’m confident that you guys are going to love these low carb lemon bars – they simply scream “IT’S SPRING BABY!” and they’ll make you believe it – no matter what time of year it is where you are.
These low carb lemon bars use a homemade lemon curd filling for a brighter, more authentic flavor than shortcut versions.
Recipe Notes:
- When zesting your lemons, make sure you don’t zest any of the white coating. That’s the pith and it’s super bitter – you just want the bright yellow rind, which is where the oils and therefore flavor are. The best tool for zesting a lemon is a microplane grater in my opinion, but a box grater on the side with the small holes in it can work too if that’s all you have.
- Use FRESH LEMON JUICE in these keto lemon bars. That bottled stuff just won’t taste the same. Since you need lemon zest anyway, you might as well take a few seconds to juice the lemons you’re zesting for a superior lemon flavor. A handheld lemon crushy thing like this one is what I use and it’s super easy.
- You will need 5 – 6 average sized lemons to make these keto lemon bars.
- When cooking the lemon curd for these keto lemon bars, DO NOT LEAVE THE POT UNATTENDED. Whisk gently but constantly until the mixture thickens enough to coat the back of a spoon, and it has lightened slightly in color. This may take 10 – 12 minutes, and it will feel like it’s never going to happen and then WHAM it’s there and it seems to be instantaneous. Be patient – I promise it’s worth it!
- Some people choose not to strain the curd after cooking, and leave the bits of grated lemon zest in the bars. It’s strictly a matter of personal preference and if you don’t mind the texture of the zest in there, it won’t hurt anything to skip that straining step.
As always I can’t wait to hear what you think! Make these keto lemon bars ASAP and report back STAT! Bonus points if you snap a pic and tag @ibreatheimhungry on IG!
(fyi said bonus points are completely useless, much like my passport in 2020.)
Print
Keto Lemon Bars
- Total Time: 40 minutes
- Yield: 16 bars 1x
- Diet: Diabetic
Description
An easy and tasty Keto lemon bar recipe that’s just as good or better than the classic – but low carb and gluten free!
Ingredients
For the Crust:
- 6 tablespoons butter
- 2 cups superfine blanched almond flour
- 1/3 cup granulated sugar substitute (I used Swerve)
- 1 tablespoon freshly grated lemon zest
For the Filling:
- 1/2 cup butter
- 1/2 cup granulated sugar substitute (I used Swerve)
- 1/2 cup fresh lemon juice (from 5 – 6 lemons)
- 1/4 cup grated lemon zest
- 6 egg yolks
- 1/2 teaspoon xanthan gum
- 2 tablespoons unflavored collagen powder (or 1 teaspoon unflavored gelatin)
Instructions
For the crust:
- Preheat the oven to 350 degrees.
- Melt the butter in the microwave or a small saucepan.
- Add the almond flour, sweetener, and lemon zest, stirring until fully combined.
- Press the dough evenly along the bottom and 1/2 inch up the sides of an 8 x 8 inch square pan. For best results line the pan with parchment paper or foil first, then you can simply lift out the completed lemon bars.
- Bake for 10 minutes.
- Remove and cool while you make the filling.
For the filling:
- Melt the butter in a small saucepan on low heat.
- Remove from heat and whisk in sweetener, lemon juice, and lemon zest until dissolved.
- Whisk in the egg yolks and return to the stove over low heat.
- Whisk continually until the curd starts to thicken.
- Remove from the heat and strain into a small bowl.
- Whisk in the the xanthan gum and collagen or gelatin until dissolved and smooth.
- Pour the filling over the pre-baked crust and spread out evenly to the edges of the pan.
- Bake the bars at 350 degrees (F) for 15 minutes.
- Remove and cool.
- Sprinkle with Powdered Swerve before serving if desired.
- Cut into sixteen 2 x 2 squares.
Notes
To see a list of my favorite low carb products and brands that I recommend for sweeteners, flours, etc. you can check out the IBIH Pantry Ingredients Page!
- Prep Time: 10 minutes
- Cook Time: 30
- Category: Keto desserts
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 2 x 2 square
- Calories: 193
- Fat: 19g
- Carbohydrates: 2g net
- Protein: 4g
More Keto Lemon Recipes You’ll Love
Keto Lemon Dressing aka. Vinaigrette
Keto Lemon Magic Custard Cake – Low Carb
Easy Keto Lemon Cheesecake – Low Carb
Keto Lemon Muffins – Low Carb and Gluten-free
58 best low carb lemon dessert recipes
Kim says
This recipe looks fabulous – I look forward to trying it after I get some ‘green can’ Great Lakes collagen. In the meantime, do you have handy the rest of the nutrition info, like grams of fiber and micronutrients (sodium, potassium, calcium, etc.)? I appreciate the net carb info but I’m trying to get a certain amount of fiber and other nutrients every day and this additional info would help. If not, I can calculate all the ingredients myself to figure it out…just thought you might already have it. Thank you.
Esther L says
Suggestions on what to do with the leftover egg whites? Thanks!
Raeesa Mumith says
If i make a batch how long would they last before they go bad?
Mellissa Sevigny says
Keep them in the fridge for up to a week, the freezer for a couple of months I would think!
Ines says
I made these bars and they turned out amazing thanks for sharing!
Leslie says
I’ve made these & loved them!
Just wondered if you think it would work with lime or key lime instead? Might have to adjust sweetener, I’m thinking.
Thanks!
Tara says
Loved them so I made these as key lime bars and they were great! Cut the zest down a bit and added 1 tsp swerve. Delish!
Harshi says
Thank you SO much for this recipe!! I made them today and they turned out amazing! I’m enjoying a piece with my tea right now. I wanted to make hubby a treat for Father’s Day, and these were just perfect. Watch me eat most of it…lol!!
Btw, I used one packet of Knox gelatine and didn’t have any issues.
I tried doing low carb without having any type of low carb treats, and crashed hard after 3 weeks. Now I’m back on and learning to make low carb desserts that will help keep me from falling off again.
Can’t wait to try out some of your other recipes!
Claire says
I made these and they turned out beautifully. However, I think the curd was too hard once cooled. I would use less gelatin next time. I also would prefer a more intense lemon flavor. Maybe more juice or leave in a small bit of zest would help with that. I would also make the curd a little sweeter.
Amber says
Hi! Do you think it matters the type of gelatin? I am about to make these, and am heading to store, but I don’t think we have Great Lakes gelatin here. I’ve never baked with unflavored gelatin. Is it powder or liquid? No clue what I’m doing with this. Any tips on what to buy would be greatly appreciated! ?
Eryn says
Hi, I was so happy to find this recipe as my Mom used to make some delicious lemon bars when I was a kid. The thought of them just makes me happy. I was eager to make these, but I didn’t have xanthan gum, so I substituted chia seeds. The filling seemed a bit soft when removed from the oven and then cooled. It tasted great nevertheless. I have placed them in the fridge overnight and they are certainly firm now. Thanks for this deliciousness.
Lisa says
Very Nice recipe but the gelatin seized up and made curds! After I strained it. So that was unfortunate. A bit extra texture. So I covered it with a layer of cream cheese and sour cream. And made a totally new desert.
Lara says
She used land o lakes green “gelatin” it doesn’t gel. So if you’re using actual gelatin, even land o lakes it won’t turn out the same. The green is great to mix in drinks and what not to get your dietary supplementation but not for gelling as it stays liquid…
MissTris says
It’s “Great Lakes” gelatin, not “Land o’ Lakes.” Just looking to avoid confusion. :-)