Blueberry Crumble Bars
There is a specific kind of summer afternoon where it is too hot to think, the kids are bored, and someone has already asked what is for snack four times. That is exactly when I start making these blueberry crumble bars. They smell like a bakery, they use the giant box of blueberries I always overbuy at the store, and they turn a sticky June day into something that feels a little bit cozy.
These are the bars I bring to every cookout, every pool day, and every time a neighbor needs feeding. They slice clean, they travel without falling apart, and they somehow taste even better cold from the fridge the next morning. Standing over the pan. In my robe. Not that I would know.
Heads up, a couple of links below are affiliate links, which just means if you grab something I get a tiny commission at no extra cost to you. Only things I actually use in my own kitchen made the cut.
Why you will love these blueberry crumble bars
One dough does double duty here, which is the whole reason I keep coming back to them. You press half into the pan for a buttery shortbread crust, pile on a quick fresh blueberry filling, then crumble the rest of that same dough over the top. No fussy layers, no separate streusel, no pulling out three different bowls you then have to wash.
They are also forgiving in the best way. Berries a little soft? Perfect, they were headed for the filling anyway. Want to stretch the pan to feed a crowd? Cut them small and suddenly you have sixteen happy people. This is a recipe that works with real life, not against it.
Blueberry Crumble Bars
Ingredients
Method
- Preheat the oven to 375F. Line a 9×13 inch baking pan with parchment paper, leaving an overhang on the sides so you can lift the bars out later.
- In a large bowl, cream the softened butter and 1 cup sugar until fluffy. Beat in the egg. Add the flour, baking powder, salt, and cinnamon, then mix until the dough comes together into soft, crumbly clumps.
- Press a little more than half of the dough evenly into the bottom of the pan to form the crust.
- In another bowl, gently toss the blueberries with 1/2 cup sugar, the cornstarch, lemon zest, and lemon juice. Spread the berries evenly over the crust.
- Crumble the remaining dough over the top of the blueberries, leaving some gaps so the fruit peeks through.
- Bake for 40 to 45 minutes, until the top is golden and the filling is bubbling at the edges. Cool completely in the pan, then chill for at least an hour before lifting out and slicing into squares.
Notes
Ingredients you will need
Nothing fancy, and you very likely have most of it already. Here is the full list so you can check your pantry before you start.
For the crust and crumble
1 cup unsalted butter, softened
1 cup granulated sugar
1 large egg
1/4 teaspoon salt
1/4 teaspoon ground cinnamon (optional, but I always)
3 cups all-purpose flour
1 teaspoon baking powder
For the blueberry filling
4 cups fresh blueberries
1/2 cup granulated sugar
1 tablespoon cornstarch
1 teaspoon lemon zest
1 tablespoon fresh lemon juice
How to make blueberry crumble bars
The full printable version with times is in the recipe card above, but here is the quick walk-through so you know what you are getting into.
Start by heating your oven to 375 degrees and lining a 9×13 pan with parchment, leaving a little overhang so you can lift the whole slab out later. Cream the butter and sugar until fluffy, beat in the egg, then add the flour, baking powder, salt, and cinnamon until it all comes together in soft crumbly clumps.
Press a little more than half of that dough into the pan for your crust. Toss the blueberries with the sugar, cornstarch, lemon zest, and juice, then spread them over the top. Crumble the rest of the dough over the berries, leaving gaps so the fruit can peek through and bubble up. Bake for 40 to 45 minutes until golden, then cool and chill before slicing. The chilling is the part everyone wants to skip. Do not skip it. That is what gives you clean squares instead of a delicious blueberry puddle.
Tips, variations, and make-ahead
A light-colored metal 9×13 baking pan gives you the most even golden top, and a roll of parchment paper is the difference between lifting these out in one clean piece and chiseling them out with a butter knife. A little microplane zester makes quick work of the lemon, and that bright pop of zest is what keeps these from tasting flat.
Frozen blueberries work in a pinch, no need to thaw, just stir in an extra teaspoon of cornstarch since they let off more juice. You can swap in blackberries or a mix of summer berries, and a handful of chopped pecans in the crumble is lovely if you want a little crunch. To make ahead, bake and chill, then keep them covered in the fridge for up to five days. They also freeze beautifully, so I usually stash half the pan for a future me who will be very grateful.
Quick recipe details
Prep time: 20 minutes
Bake time: 40 to 45 minutes
Cool and chill: about 1 hour
Servings: 16 bars
Storage: covered in the fridge up to 5 days, or freeze up to 3 months
The takeaway
These blueberry crumble bars are the easy, crowd-pleasing kind of summer treat that makes you look like you have it all together, even on the days you very much do not. One bowl, one pan, a box of blueberries, and you have got dessert for the whole week. If you make them, come tell me how they turned out, and whether you ate one cold over the sink like I do. Drop it in the comments, I always have room for more blueberry talk.
So glad you are here.
xo, Pam
