Blueberry Lemon Crisp Bars

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These bars have a buttery, sweet oat crisp layer on the top and bottom, with a blueberry lemon filling in between that is irresistible and will have you going back for more! It is the perfect summer treat! 

This recipe was inspired by a traditional blueberry crisp, but I wanted to take it up a notch and add in some bright citrusy notes with the lemon, and have a thick layer of the buttery oat topping that you can pick up and eat as a bar. And this recipe did not disappoint! It is really easy to make and looks so beautiful with the deep purple blueberry layer. 

When I was recipe-testing these bars, my husband and father-in-law were my taste testers. They took one bite and said, “These should be called oh-my-gosh-bars!” Because they just that good! We ate the whole batch in one night!

Tips to make the Blueberry Lemon Crisp Bars

1. It is important to let them completely cool before removing the parchment paper from the pan or cutting into them. Otherwise, they will not hold the bar shape. 
2. Add them to the fridge for at least one hour to ensure they are 100% cooled. Plus chilling in the fridge will solidify the butter and ensure they will hold their shape. 
3. My intention was to create a bar shape, but this recipe is just as good if you eat it fresh from the oven! You would not be able to pick them up and eat them, but it is also so good warm with a scoop of ice cream on top!

Tools to make the Blueberry Lemon Crisp Bars

Lemon Zester– I think this is an underrated tool in the kitchen and every home cook needs one! You can use it to zest citrus or to finely grate parmesan cheese. You can also use it to finely grate garlic or fresh ginger. I reach for this tool often in my kitchen!

Square baking pan- I used an 8×8 glass baking pan. If your square pan is slightly bigger, that’s okay! You will just have thinner bars. 

Parchment paper- This is necessary to use in order to easily lift the bars out of the pan. 

Ingredients for Blueberry Lemon Crisp Bars

For the crisp/crust of bars

• Flour – all-purpose flour, I always prefer unbleached flour because it is less processed. 
• Oats- Old Fashion Rolled Oats
• Butter – Melted unsalted butter, if you only have salted butter you can substitute for that but reduce the added salt. Melting the butter first helps it mix into the ingredients more easily. 
• Salt – Redmond Real Salt is my favorite 
• Lemon zest – of one lemon
• White sugar – I like to use cane sugar rather than granulated white sugar
• Brown sugar – this adds some moisture and a deeper flavor. 

Blueberry Filling

• Blueberries- fresh blueberries
• Sugar – cane sugar
• Corn starch – To thicken the blueberry filling
• Lemon juice – Juice from one lemon, about 2 tablespoons 
• Lemon Zest – of 1 lemon 

What type of oats can you use for this recipe?

This recipe calls for rolled oats or old-fashioned oats. You can substitute for quick-cooking oats if that is what you have. These oats are thinner than old fashion oats but I have made this recipe with them as well and they work fine! Really, any oats you have on hand besides steel-cut oats will work.

How to make Blueberry Lemon Crisp Bars

Preheat your oven to 350F degrees. 

Zest one lemon and add the zest to a medium-sized bowl. Add in the cane sugar and using your fingers, rub the zest into the sugar. This helps distribute the oils from the zest into the sugar and distribute the lemon flavor throughout the rest of the ingredients.

Then add in the remaining ingredients for the crisp- brown sugar, flour, oats, salt, and melted butter. Mix to thoroughly combine. 

Next, add the lemon zest and cane sugar to a bowl and rub together. Then, add the remaining ingredients for the blueberry filling into a medium bowl and toss it to coat it evenly. 

Line an 8×8 square baking pan with parchment paper. (The parchment paper is needed to easily lift the bars out of the pan.)

Add about ⅔ of the crisp to the bottom of the pan and using your fingers or a spatula, press the crisp down into the pan firmly to create an even layer. 

Next, add in the blueberry filling and spread it out evenly. 

Finally, add the reaming crisp on top in an even layer. It’s okay if there are a few holes here and there on top. 

Bake for 45-50 minutes or until the top is golden brown. 

Remove from the oven and let it cool completely before cutting. After it is almost completely cooled, add it to the fridge for an hour or two to help it stay in a bar shape. 

If the bars are too warm, they will fall apart when you cut into them. They are also really delicious warm and eaten with a fork! You can skip the cooling process if you do not want to cut them into a bar shape. Just use a spoon to get out of the pan and top with vanilla ice cream if you desire and enjoy!

To cut them into bars: When it is completely cool, lift the bars out of the pan with the parchment paper. Remove the parchment paper and cut into 9 squares. And enjoy!

How to store the Blueberry Lemon Bar

Store in an airtight container in the fridge. If the bars stay cool they will hold their bar shape. Or, you can pop them in the microwave for a few seconds to warm but at this point, you will need to eat them with a fork. 

More fruit-filled desserts 

Tart Cherry Crisp– made with tart cherries and a buttery cinnamon oat topping. 

Tart Cherry Pie– Homemade pie crust filled with tart cherry filling 

Peach Pie- The filling is made with fresh or frozen peaches and is made with a homemade butter pie crust.