Spread half of the mixture (I weigh mine to get even halves) onto an ungreased 15x10 jelly roll pan. Spread pie filling over the top of the batter. Drop remaining batter onto the pie filling layer by spoonfuls.
21 ounces blackberry pie filling
Bake for 45 minutes or until golden brown. Do not under bake. Remove to a wire rack.
Combine powdered sugar, melted butter, and lemon juice. Drizzle over warm bars.