Lemon Crumb Bars are dessert bars filled with lemon filling and flavor in between two layers of an oatmeal crust. They are one of the BEST lemon desserts I have ever had! If you love lemon desserts, be sure to also try my Lemon Bars and Lemon Brownies!

Stack of Lemon Crumb Bars

Lemon Crumb Bars

When life gives you lemons, make these Lemon Crumb Bars! They start with the oat crust from my Apple Cream Cheese Bars (without the cinnamon). And then the oatmeal layers are separated by a lemon filling that you can taste in every bite. There is a fantastic fusion of texture and flavor in these bars… they are unlike any other lemon dessert on my website!

Adding Lemon Filling to Lemon Crumb Bars

Bars Ingredients

There are two parts to this recipe–the oatmeal layers and the lemon filling.

Oats: Use quick-cooking oats. Quick oats are more processed than old-fashioned oats, which allows the oats to cook faster. 

Sweetened Condensed Milk: Be sure to check the labels carefully when buying sweetened condensed milk. Do not use evaporated milk in this recipe.

Lemon Juice: Use freshly squeezed lemon juice from about 5 lemons for the best taste. We tested this recipe using bottled lemon juice, but there was a difference in flavor. I will get to that later.

Lemon Zest: For even more lemon flavor in each bite, add a teaspoon of lemon zest to the filling.

Sprinkling Crumb onto Lemon Crumb Bars

Freshly Squeezed Lemon Juice vs. Bottled Lemon Juice

As I stated earlier, we tested these bars two times–one time using freshly squeezed lemon juice and the second time using store-bought juice. When taste-tested side by side, the bars that were made with freshly squeezed juice won by a landslide. Of course, there is always one odd one out, as they say, who preferred the bottled juice. 

If using the bottled juice, you will notice more of an artificial lemon flavor compared to freshly squeezed juice. However, if you only have bottled juice, the bars are still lemony and tasty.

How to Store Lemon Crumb Bars

Lemon Crumb Bars can be stored at room temperature in an airtight container for up to 2 days. If you store them in the refrigerator, they will last up to 5 days. You can freeze the bars for up to 3 months. 

Fork Taking a Bite of Lemon Crumb Bar on a White Plate

More Delicious Bars

4.73 from 11 votes

Lemon Crumb Bars

Prep Time 30 minutes
Cook Time 25 minutes
Chilling Time 1 hour
Total Time 1 hour 55 minutes
Lemon Crumb Bars are dessert bars filled with lemon filling and flavor in between two layers of an oatmeal crust.


Oat Crust

  • 1 cup (80 g) quick-cooking oats
  • cups (180 g) all-purpose flour
  • 1 cup (200 g) light brown sugar, packed
  • ¼ teaspoon baking soda
  • ¼ teaspoon baking powder
  • ¾ cup (1½ sticks / 170 g) unsalted butter. melted

Lemon Filling

  • 1 can (14 ounces) sweetened condensed milk
  • 2 large egg yolks
  • ½ cup (115 g) freshly squeezed lemon juice, about 5 lemons
  • 1 teaspoon lemon zest
  • teaspoon kosher salt


  • Preheat oven to 350°F and line a 9×9-inch pan with parchment paper.

Oat Crust

  • In a large bowl, combine oats, flour, brown sugar, baking powder, and baking soda. Pour melted butter over the mixture and mix together until crumbly. Be careful not to overmix so it will be crumbly for the top later.
  • Measure out ½ of the mixture (about 2 cups), and set it aside to reserve for topping.
  • Pour the remaining mixture into the lined baking dish. Press firmly to the bottom of the pan.
  • Bake 12-15 minutes, or until a golden brown. Set aside to cool slightly while you make the lemon filling.

Lemon Filling

  • In a large bowl, add sweetened condensed milk, eggs, lemon juice, lemon zest, and salt. Mix until smooth and creamy.


  • Spread lemon mixture over the top of the baked oat mixture.
  • Crumble the reserved oat mixture over the top.
  • Bake 20-25 minutes or until edges are golden brown.
  • Let come to room temperature and then refrigerate 1 hour before serving. (Best enjoyed at room temperature.)

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Meet Amanda Rettke

Amanda Rettke is the creator of I Am Baker, and the bestselling author of Surprise Inside Cakes: Amazing Cakes for Every Occasion – With a Little Something Extra Inside.Over the course of her 15+ year blogging adventure, she has been featured in and collaborated with the Food Network, New York Times, LA Times, Country Living Magazine, People Magazine, Epicurious, Brides, Romantic Homes, life:beautiful, Publishers Weekly, The Daily Mail, Star Tribune, The Globe and Mail, DailyCandy, YumSugar, The Knot, The Kitchn, and Parade, to name a few.

Reader Comments

  1. I want to make these bars. Our condensed milk is in 10 ounce cans. Howcan I adjust other filling ingredients. Ty

  2. I want to make these bars. Our condensed milk is in 10 ounce cans. Howcan I adjust other filling ingredients. Ty first time asking this

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