1350 degree oven. Spray 9 x 13" pan with cooking spray. Layer, don't mix, the pineapple, then the blueberries (if using frozen, no need to defrost them), and dry cake mix. Drizzle melted butter over all; sprinkle with brown sugar and top with chopped pecans. Bake 40 - 45 minutes, until top is bubbly and cake topping is cooked through. ENJOY!