BASE:
3 lb. 10-1/2 ounce or 3 quarts 3 cups Flour
1-1/2 tablespoon Salt
3/4 tablespoon baking soda
9 cups Rolled Oats
3 lbs margarine
LIGHT SUGAR FILLING:
7 quarts + 1 cup Marion Blackberries IQF or fresh
1-1/2 cups Sugar (or more to personal preference)
6 tablespoon Cornstarch
2-1/2 tablespoon Water
1 teaspoon Salt
2-1/2 tablespoon Lemon Juice
For Topping
Combine all ingredients. Mix until crumb-like consistency. Scale approximately 3-1/2 lb. mixture into four steam table pans, 12″ x 20″ x 2″. Pat mixture firmly into bottom of pan. Sprinkle remaining crumbs over filling. Bake at 350 degrees for approximately 30 minutes.
For Filling
Combine berries and sugar. Heat until well blended. Slowly add cornstarch/water mixture and salt. Cook until thickened, approximately 5 minutes. Add lemon juice. Remove from heat.
Serves 50