It's a really easy dessert, as desserts go. We have learned that we like a little bit of applesauce mixed with the blackberries. Straight blackberries tend to be a little bit too tart. I use my basic shortbread recipe for the topping.
Apple and Blackberry Crumble
1 lb. of fresh or frozen blackberries
1 jar of applesauce
8 oz. plain flour
4 oz. softened butter
2 oz. cane sugar
Mix the blackberries and applesauce in a 13"x9" baking dish. Mix the flour, butter and sugar in a bowl (I use a mixer). Sprinkle the crumble over the fruit. Bake for 30 minutes at 350 degrees. Serve warm with a scoop of ice cream!