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
Ainsley says
Greetings Mellissa <3
I was just nomming on your bison beer braised meatballs with cauliflower mash yesterday and was actually happy swaying from how good they were, I did use regular old ground beef but it was still amazing. Especially on the second day.
But on this recipe I made it a few weeks ago and kept forgetting to ask, my bars are amazing and taste fairy level amazing when heated up but when I tried to eat them cold the yellow lemon part would fall off of the crust. To avoid this would I just use less gelatin? I used the Great Lakes one.
Mellissa Sevigny says
Hi Ainsley, glad you’re enjoying the meatballs! Regarding the lemon bars, it’s weird that the lemon part didn’t bond to the crust. I wonder if it IS an issue of the gelatin. Was it super hard, because if so that could be it? Or maybe if the cookie layer baked too much they didn’t bond together after you added the lemon curd. I’m totally stumped on that one but I would try it next time with less gelatin and see what happens. Or omit the xanthan gum and keep the gelatin the same. Glad they tasted good though!
Ainsley says
Hmm…I believe experiments are required…for science. I may have baked the crust too long or maybe my crust was too thick, because now that I’m looking at the pictures mine was much thicker. I failed to follow directions. Next time I’ll omit lessen the gelatin and cook the crust longer.
Thanks so much =)
richard schmidt says
these look so good. i want to make them for my Quaker meeting this Sunday, but i dont use sugar. can i substitute honey or agave or maple syrup instead?
Mellissa Sevigny says
Any of those could work but I’m not sure of the quantities.
richard schmidt says
cooks.com says either 1/2 or 2/3 cup honey equals 1/2 cup granulated sugar-but then also says to reduce the other liquids.now THAT sounds like it could be tricky
Mellissa Sevigny says
Yes, I think you’ll have to experiment a bit. Agave is the sweetest and will probably take up the least amount of volume so you might get away with a little less since there isn’t a lot of room to reduce liquids in this recipe. Let us know if you figure out a way to make it work!
Ruth Hadlock says
Great recipe! The crust is soo good, I have a question about the filling – did anyone else’s filling turn to rubbers with 2 tbsp gelatin? I used the powdered gelatin in the box. Wondering if next time I should use 2 tsp. instead of tbsp? Thanks for then yummy recipe! I loved all that real lemon! I didn’t event strain it because I wasn’t sure what I was supposed to be straining!
Mellissa Sevigny says
Hi Ruth! I used Great Lakes Gelatin which may act differently than the powdered gelatin in the box so if you got a rubbery texture then definitely use less next time! Glad you liked the flavor! I strain out the lemon zest to get a smoother texture in the bars, but it’s definitely not a requirement if the texture didn’t bother you! Thanks for weighing in!
Audrey says
I made these Lemon Bars yesterday…but made them into little tarts using muffin tins & altered the crust a bit by using Coconut Flour…but they turned out FANTASTIC!! Thanks so much for the recipe!! :)
Mellissa Sevigny says
Little tarts sounds adorable – totally stealing that idea Audrey! Glad you liked them!
Peggy says
Hi Melissa,
Thanks so much for sharing all your hard work and delicious recipes with us. I tried these Lemon Bars and they were just like the real deal, so I was very excited to be able to have them again after eliminating sugars and grains from my diet. They were light, tangy and felt like a great Spring treat! I did have a few problems while making them though that I wanted to ask you about. First of all you said 1/4 cup lemon zest and I wondered if that was the correct amount. I had to use 8 lemons and I was still shy of that amount. Also, when I went to strain the lemon curd, all of the zest was caught in the strainer, is it supposed to do that? Also, as I was cooking the filling it started to turn a putrid green color and I don’t know why. I had to add a bunch of yellow food coloring to it and they still turned out an unattractive yellow-green color. They still taste great, but I am wondering what I may have done wrong since yours are such a pretty yellow color. Thanks for your help.
Mellissa Sevigny says
Hi Peggy! I’ve eaten the curd without straining it but not everyone likes the texture of all the lemon zest in it which is why I recommend straining it out. 8 lemons should have given you more than enough zest – were you using a micro plane grater made for zest ink, or something else? Regarding the color, sounds like it may have reacted with your pan. Acidic foods like lemon will turn a weird green color in a metal pan sometimes. Try it in enamel or a coated nonstick pan next time and you should get the bright yellow natural color with no need for food coloring! Hope that helps, glad they tasted good at least!
Brenda says
Okay, found my Easter dessert. Thanks so much. If these are even half as good as the raspberry cheesecake bars, I’m going to be one happy camper. I’ve been following the menu plans (on week 3, now) and I have to say that EVERYTHING I’ve made from your site is delicious. EVERTHING. That ususally doesn’t happen. I cook a lot, and sometimes I look at ingredients you have listed and a little doubt comes into my mind, but it’s always swept away by the final product. I’m dying to make the General Tso’s meatballs again, and the chicken salad you just posted looks incredible. I’ve lost about 7 lbs, and most importantly, busted through a number on the scale that I haven’t been able to breech in over a year. Thank you again for all your work. It is MUCH appreciated.
Mellissa Sevigny says
Congrats on being the boss of your scale, so happy that the plans are working for you!!! As for these lemon bars I like them even more than the cheesecake bars so you’ll have to know what you think once you try them!!!
Debbie says
Can you use the green can gelatin or do you need the red can kind? Thanks.
Mellissa Sevigny says
I used the green can gelatin Debbie and it worked great!
Leslie says
I wondered about this… The green can of Great Lakes is collagen, not gelatin, so it doesn’t set like gelatin. Maybe that’s why folks who used gelatin had issues? I am definitely making these this weekend, but they will be coming to work with me Monday morning so I don’t eat them all :)
Amy says
I had a question about this too. I’ve made this twice and used Knox Orinal Gelatine. Is there an advantage to using the one listed in the recipe?
Jammie says
Do you have to use gelatin in the recipe. Are there any substitutes?
jessie says
is the filling firm enough to stand up without the crust?
Mellissa Sevigny says
It’s pretty firm but you’d have to chill it well and probably cut it into one inch squares.
Eric says
Welcome to spring(?) in the Hudson Valley! I’m just north of you in Dutchess County, and the view out of my window is still as arctic as yours. Sigh. Love lemon bars, though, so these will help to get me through the next few days as the crud melts. Thanks for posting, and good luck with the rest of your moving chores.
Mellissa Sevigny says
Thanks Eric!!! It’s above freezing today so I’m optimistic that the snow bank out front will be gone soon! Hope you like these!!!
Jan says
Welcome, back, Melissa :) These look great. I’m going to have to get over the reluctance to separate eggs for recipes and make these.
Mellissa Sevigny says
It’s worth it jan, promise!!!!