4 cups of blueberries are in these scrumptious Blueberry Crumb Bars. Blueberry heaven! 10 ingredients & 10 minutes to make.
Preheat oven to 350°F (175°C). Line a 9x13 baking dish with parchment paper and set aside.
Put flour, sugar, baking powder, and salt into a food processor and pulse 1-2 seconds to combine. Cut butter into a few chunks and add to the dry ingredients. Pulse a few seconds into coarse crumbs with pea sized butter flakes in it. Add egg + egg yolk and pulse a few seconds just until combined. The dough should be still crumbly.
Transfer 2/3 of the crumbs to the prepared baking pan and press them evenly into the pan with your fingers.
In a large bowl, stir together blueberries, sugar, cornstarch, lemon juice, and vanilla* just until combined. Spoon filling including the liquid evenly onto the dough in the baking pan. Crumble the remaining dough evenly on top of the blueberry layer. Bake for about 45 to 50 minutes or until golden brown on top. Let cool in the pan completely before cutting. Store leftovers in an airtight container at room temperature up to 2 days.
*First, cut off the straight end of the vanilla bean. Then place the tip of your sharp knife below the curled end and cut the vanilla bean through the middle of the bean lengthwise. Although you don't need to cut it all the way through, it's ok when you do so. Then open the vanilla bean and scrape out the flavorful seeds with the back of your knife. Then just use the seeds.