1½ cups sugar, divided
1 tsp. baking powder
3 cups all-purpose flour
¼ tsp. salt
Zest of 1 lemon
16 tbsp. cold unsalted butter, cut into pieces
1 large egg
4 cups fresh raspberries
4 tsp. cornstarch
Juice of 1 lemon
Preheat the oven to 375° F. Grease a 9 x 13″ pan; set aside.
In a medium bowl, combine 1 cup of the sugar, the baking powder and flour. Mix in the salt and the lemon zest, and stir together with a fork. Cut in the butter and egg with a pastry blender until the largest chunks are about pea-sized. The mixture should be crumbly without much loose flour. Spread about half of the dough mixture in an even layer over the bottom of the prepared pan and press down firmly to form the bottom crust.
In another bowl, stir together the remaining sugar, cornstarch and lemon juice. Gently mix in the raspberries with a rubber spatula until combined. Sprinkle the berry mixture evenly over the crust. Crumble the remaining dough over the top of the berries.
Bake for about 45 minutes or until the top is slightly golden brown. Cool completely before cutting into squares and serving.