Homemade Sourdough Grapenut

Homemade Sourdough Grapenuts..
A cereal eaten with milk or used as granola.
The recipe below is for 1 batch which makes close to 6 quarts. You can put it freezer bags or containers and freeze them. One batch last my family of 4 up to 2 months.
2 cups raw cane sugar
2 teaspoons blackstrap molasses
2 cups sourdough
4 cups buttermilk
3/4 cup melted butter
2 teaspoons salt
1 teaspoons maple flavor
1 tablespoon vanilla
1 tablespoon soda
11-12 cups spelt flour or flour of choice
Combine sugar, molasses, sourdough starter, buttermilk, and butter in a large bowl. Stir in salt, vanilla, maple flavor, flour and soda. Spoon into three grease cake pans. Cover with saran wrap and set in a cool place for at least two hours. Bake at 350° for 45 minutes or until cake is dry. Cool and crumble. Lower oven temperature to 250°. Bake crumbs on cookie sheets until browned and crispy. I spread my crumbs into four cookie sheets and bake them for 90 minutes during every 20 minutes. They will get crunchier as they cool.