The Best Low-FODMAP Lemon Square / Lemon Bar Recipe; Gluten-free

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I love dessert recipes that incorporate the citrus tang of lemon.  To me, nothing could be better than a sweet and tart creamy flavor, layered with a buttery crunchy crust.  Just like my low-FODMAP Key Lime Pie recipe, these low-FODMAP Lemon Squares aka Low-FODMAP Lemon Bars are sugary, gooey, tangy and crumbly.  A perfect combination of flavors.

While we don’t usually consume lemons in large quantity, the fruit of the lemon is a wonderful source of vitamin C, folate, as well as limonens- a phytonutrient that is found mainly in citrus fruits.  These compounds help in digestion and absorption of other key nutrients and may also have cancer-fighting properties.

These low-FODMAP Lemon Squares are so sunshiney, they will brighten up every table.  They taste as fresh as a spring day.  I bet this low-FODMAP Lemon Squares recipe will be the best you will ever have.  Plus these low-FODMAP Lemon squares are simple to make, and gluten-free.

Enjoy over 300 more low-FODMAP recipes on the blog, including low-FODMAP Dream Bars, low-FODMAP Strawberry Oat Bars or low-FODMAP Pumpkin Bars.  Or if you love lemon as much as I do- check out the low-FODMAP Lemon Poppyseed Layer Cake with Lemon Curd or my Starbuck’s Copycat Iced Lemon Loaf.  So delicious!

Be healthy and happy,

Rachel Pauls, MD

The Best Low-FODMAP Lemon Square / Slice / Bar Recipe; Gluten-free

Although this recipe has not been tested, a single serving should be low-FODMAP based on the ingredients

Serves 16

Prep time: 15 min

Bake: 15 min and 20 minutes

Total time: About 1 hour

Bake 350 F


For low-FODMAP Lemon Squares Crust

  • 1 cup Authentic Foods GF Classical Blend flour (my favorite low-FODMAP flour- check out my low-FODMAP bake off for results); or your preferred low-FODMAP all purpose gluten-free flour
  • 1/4 cup granulated sugar
  • 1 tsp xanthan gum, if not incorporated in your low-FODMAP flour selection already
  • 5 tbsp cold unsalted butter (I have not tried this with vegan spread, shortening or coconut oil, but feel free to let me know if you do!)
  • Vegetable shortening for greasing

For low-FODMAP Lemon Squares filling

  • 3 large eggs
  • 3/4 cup sugar
  • 2 tbsp Authentic Foods GF Classical Blend Flour (*see note above)
  • 1/2 tsp baking powder
  • 1/8 tsp salt
  • 1/3 cup freshly squeezed lemon juice (about 2 medium lemons)
  • 2 tsp lemon zest
  • 1/2 tsp pure lemon extract

For low-FODMAP Lemon Squares garnish:

  • Confectioner’s sugar for sprinkling


  • Preheat oven to 350 F
  • Grease a 8 inch square pan and line with parchment paper or aluminum foil, grease this also
  • Place low-FODMAP flour, sugar and xanthan gum in large bowl of electric mixer with flat paddle
  • Add butter and mix on low until dough is crumbly
  • Press out crust in bottom of prepared pan until smooth (I like to use the bottom of a measuring cup)
    • The dough should stick together when you press it out
  • Bake for about 15 minutes until lightly golden
  • Prepare filling while crust is baking
  • Beat eggs in the large bowl of mixer at high speed using whisk paddle until foamy and light
  • Add flour, sugar, baking powder, salt and mix
  • Add lemon juice slowly then lemon zest, followed by extract
  • Beat until well blended
  • When finished baking, remove crust from oven. Let it stand about 5 minutes to cool slightly
  • Pour prepared filling over baked crust
  • Place back into oven for 20 minutes until set
  • Cool on wire rack completely
  • Dust with confectioner’s sugar before serving
  • Refrigerate unused portions in covered container

  • These are so pretty…

  • I love low-FODMAP Lemon Bars aka Lemon Squares!

Comments Rating 5 (8 reviews)

23 Responses

  1. Delicious

    I am adjusting to a low fodmap diet. While incorporating new recipes that will also satisfy the rest of the family I found this recipe. I do have a question. Should the crust be cooled before adding the filling? Maybe I did not bake the crust long enough. When I poured the filling onto the crust and the filling pushed the crust off the bottom of the pan in the middle. I am not sure and trying to learn to bake with gluten free flours so any advice would be helpful. Thank you for the delicious but not as pretty as yours dessert. I will keep trying!

    1. Kelly,
      Thank you for your question, we totally understand how you feel! Baking gluten-free takes a little practice and you may find the tips on our bake-off blog to be helpful. We do prefer the low-FODMAP, gluten-free flour we use because not all flours behave the same.
      It doesn’t sound like the problem was the crust was too warm, although you may prefer to let it stand about 5 minutes before adding the filling. It may be that you did not press the crust down enough in the pan so it was too dry? Even though the crust will seem very crumbly, it should adhere together when you create the bottom crust. Hope that helps! Good luck and check out our latest low-FODMAP Pecan Pie Bar recipe too 🙂

  2. Better than Expected!

    I used buckwheat flour and coconut oil instead of butter, and it came out better than I had hoped. We ate it all!

    1. Natasha!
      We are so thrilled to hear from you!
      Thank you so much for posting your comment and review. It is very helpful to hear how your substitutions worked out for other readers. We hope you continue to stay in touch and enjoy all of our recipes. Have a wonderful day?

  3. it would be really good idea to have the nutritional fax with your recipies l think people would use this more

    1. Hey Anonymous. How about expressing some appreciation for what is here instead of criticizing. These recipes are great and I’m sure Dr. Rachel could use some encouragement and gratitude for all her efforts! Why don’t you download a nutrition app if you want nutritional information.

  4. Best ever

    I nearly cried when eating one of these. They’re absolutely phenomenal. I even tweaked the recipe and used very cold soy free earth balance and buttermilk made with almond milk and vinegar. If I hadn’t made it myself I would have immediately spit it out, asking if it was gluten free and low fodmap. Thank you, thank you, thank you!

    1. Katelyn,
      Amazing to hear from you. We can’t wait for you to try more of our delicious low-FODMAP recipes. You won’t believe your tastebuds! They are just like their counterparts, but without the high-FODMAP ingredients.
      Stay in touch with us, please!!

  5. Hi there

    When you say
    “ Pour prepared filling over baked crust
    Place back into oven for 20 minutes until set”

    Do you mean bake the filling at 350f for another 20 minutes? Or just place in a warm oven that is off?


    1. Thank you for the question,
      The oven should still be on at the temperature outlined above, and you should bake it for the additional time.
      Good luck!

  6. Can you do these without the lemon extract? That’s the only ingredient that is hard to find without being synthetic tasting!

    1. Robin,
      You certainly can do so, but they may not be as ‘lemony’. That is a matter of personal preference 🙂
      If you can find pure lemon oil, then that also works but you would need to adjust the amount (the oil tends to be more potent). Let us know how they are!

    2. Love these!

      I’ve made these a few times and they are so amazing. I’m a sucker for lemon. The first time I made them, I didn’t have lemon extract so I added a ton more zest and lemon juice. And they were perfect! I also use vegan butter with no issues at all. ??

      1. Thank you so much Amy!
        We have several other low-FODMAP lemon recipes, just search our blog for other inspiration! Have a great day ?

  7. Yummy

    I’m new to low fodmap but Dr Rachel’s recipes and products have been a LIFE savor! I’m still working on perfecting my gluten free baking but I loved these!

    1. Stephanie!
      Love this! People like you are the reason we love sharing our recipes. Start in touch and keep baking!!?

  8. Bit of Advice Please

    Hi! I gave it 5 stars cos it tastes divine. Nevertheless, my bars aren’t as yellow as yours, probably because I beat the eggs till they were foamy and light yellow. Just wondering how you get yours such a rich looking yellow. Perhaps I’ve beaten the eggs too long? Thanks for your aid!

    Don’t you worry! These will nevertheless be gobbled up in no time. Yummy as!

    1. Hi MrsMinniver!
      It may have just been that our lemon juice was darker, or the lighting for the photos enriched our colors. We think you did the egg step correctly. Glad you enjoyed!

        1. Hi there,
          We haven’t tried to freeze the bars, but it would probably work. Thanks for the question!

  9. A few tweaks

    I had to make a few changes because I didn’t have the whisk paddle. So I combined the butter into the flour mixture as you would making pastry with the tips of your fingers. I used another sheet of baking paper over the top to press the mixture into the baking tin. It didn’t stick and became nicely compressed.
    I also used extra lemon juice and extra zest as I didn’t have lemon extract. Yumbo

    1. Liz,
      Awesome! Love hearing how great these turned out, even with a different technique. Thanks so much for commenting 🙂

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