01 -
Preheat oven to 350 degrees and line a 9x13 baking dish (or a 9x9 if you like thicker bars) with parchment paper.
02 -
In a standing mixer, add the flour, sugar, and lemon zest. Mix until combined.
03 -
Add in the cold cubed butter and mix. Using your fingers or a fork, break up the butter into smaller pieces and continue mixing until incorporated.
04 -
Add in the eggs and mix until a crumbly dough comes together.
05 -
Press half of the dough into the bottom of the prepared baking dish to form the crust layer. Set aside.
06 -
In a large mixing bowl, combine the halved blackberries, lemon juice, cornstarch, and sugar. Mix until well combined and berries are evenly coated.
07 -
Pour the blackberry mixture over the crust and spread it evenly with a rubber spatula.
08 -
Crumble the remaining dough over the blackberry filling to create the top layer.
09 -
Bake in the preheated oven for 35-40 minutes or until the crumble appears slightly golden brown.
10 -
Remove the baking dish from the oven and set aside to cool completely before cutting into bars and serving.