Pour the batter into the prepared pan and smooth it out. Evenly pour the fruit mixture on top of the batter, juice and all.
Sprinkle on the optional streusel. Use as much or as little as you'd like. Any leftover streusel mix can be frozen for another time.
Bake in the center of the pre-heated oven until the filling is bubbling and the batter is deep golden brown and set.
Serve warm with vanilla ice cream or whipped cream.