2 ½cupsall-purpose flour, spooned and leveled,divided
⅓cuplight or dark brown sugar,lightly packed
1tspcoarse Kosher salt(if using table salt, use half the amount)
1tspbaking powder
Instructions
Filling
Combine all the filling ingredients in a saucepan. Over medium heat, bring the mixture to a boil, while stirring frequently. Once it starts to thicken and bubble, stir constantly and cook for another 30-60 seconds.
Set the filling aside to cool slightly while you make the crust and crumble topping.
Crust and Crumble Topping
Preheat the oven to 350. Line an 8×8 inch square baking pan with parchment paper.
In a small saucepan, melt the butter over medium heat. Continue to cook the butter, swirling the pan occasionally, until nutty brown solids form on the bottom of the pan. This should take about 5 minutes.
Meanwhile, in a bowl, combine 2 cups of the flour (reserving 1/2 cup of flour for later) with the brown sugar, salt and baking powder.
As soon as the butter is browned, use a spatula to scrape the bottom of the pan to scrape up all the browned bits. Pour the hot butter over the flour mixture. Stir with a spoon to form it into a soft dough.
Scoop 2/3 of the dough (reserving 1/3 of the dough for the crumb topping) into the prepared baking pan, and use your hands to press the dough evenly into the bottom of the pan. Bake for 20 minutes.
Take the reserved 1/2 cup of flour and add it to the remaining 1/3 dough. Use a fork or pastry cutter to work the flour into the dough until you have a crumbly topping. Set aside.
After the crust bakes for 20 minutes, take the pan out of the oven. Pour the blueberry filling over the hot crust, then sprinkle the blueberries with the crumb topping. Bake for another 30 minutes, until the filling is bubbling and the topping is golden brown.