Blackberry Crumble
["2 qt. blackberries or plums (fresh or frozen)", "2 c. sugar", "5 Tbsp. cornstarch", "1 tsp. vanilla", "1 c. margarine or butter", "1 1/2 c. brown sugar", "1/2 tsp. salt", "2 c. uncooked oatmeal", "1 1/2 c. flour", "1 tsp. baking powder"]
["Cook first 4 ingredients together until thick.", "It may be necessary to break fresh berries to produce juice.", "Set aside this filling mixture."]
["blackberries", "sugar", "cornstarch", "vanilla", "margarine", "brown sugar", "salt", "oatmeal", "flour", "baking powder"]