Cup of Yum
1. Preheat oven to 350F (175C) and lightly butter the sides and bottom of a 9x13 glass baking dish¹. Set aside.
2. In a medium-sized, heavy-bottomed saucepan, combine 3 ½ cups strawberries (490g), sugar, cornstarch, lemon juice, and salt over medium-low heat.
3. Stir frequently until strawberries release their juices (about 5 or so minutes), then increase heat to medium/medium-high and bring mixture to a boil, stirring constantly.
4. Boil for one minute (still stirring) then stir in remaining strawberries. 
5. Cook for another minute, then remove from heat. Add butter and stir until butter is melted. Allow mixture to cool while you prepare your crumble mixture.

For Crumble

1. I strongly recommend using a food processor and not a pastry cutter for this step, as it’s a very dry mixture that will take a long time to work to the proper consistency manually.
2. To prepare crumble layer, combine flour, granulated sugar, brown sugar, baking powder, cornstarch, and salt in the basin of a food processor. Pulse until combined.
3. Scatter butter pieces evenly over flour mixture and pulse until mixture resembles coarse crumbs.
4. Add egg and vanilla extract and continue to blend until mixture is just beginning to cling together and holds together if you press the dough together with your fingers.
5. Pour approximately one half of the crumble mixture into your prepared pan and use your hands or the back of a spoon to evenly press the crumble mixture into your pan (see image in post for visual).
6. Pour strawberry mixture over crumb crust and spread so that it is evenly distributed. Use your hands to scatter remaining crumble mixture evenly over the top of the strawberry layer.
7. Transfer to 350F (175C) oven and bake for 50-60 minutes or until the top layer is just beginning to turn golden brown.
8. Allow to cool for 1-2 hours before slicing and serving (strawberry crumb bars will fall apart if sliced while they’re still warm, but they do taste good warm and messy topped with vanilla ice cream!).