This is like a crisp or cobbler that takes not even 5 minutes to get into the oven! What I like about this Blueberry Dump Cake as opposed to others on the site is that it uses fresh or frozen blueberries rather than blueberry pie filling
In a 13 x 9" baking pan coated with cooking spray, spread the pineapple and blueberries over the bottom of the pan. Sprinkle evenly with the cake mix and brown sugar. Drizzle the butter evenly over the top.