- Crust
- 2 1/2 cups rolled oats (not instant)
- 3/4 cup all purpose flour
- 1/2 cup whole wheat flour
- 1 cup cold butter or margarine cut in cubes
- 3/4 cup packed brown sugar
- Filling
- 3 cups fresh blueberries
- 1/2 cup granulated sugar
- 1/3 cup lemon juice
- 4 teaspoons cornstarch
Prepare a 9 inch square pan by lining with parchment paper to form a sling. Spray with cooking oil.
Combine blueberries, sugar, and lemon juice in a saucepan and bring to a boil. Reduce heat and simmer for 10 minutes.
Add cornstarch to 2 tablespoons of cold water and whisk into the blueberry mixtures and return to a boil, stirring until thickened. Remove from heat, cover with wrap and refrigerate until cool.
Combine the oats, flours and sugar in a large bowl. Cut in butter or margarine with a pastry blender until mixture resembles course crumbs.
Press half of the oats mixture into the prepared pan and spread with blueberry filling. Sprinkle with remaining oat mixture and press lightly to make crumble topping.
Bake squares in a 350 degree F oven for 45 minutes or until done. Cool completely before cutting into squares.