Preheat oven to 350 degrees and grease a 9×13 baking pan/casserole dish.
In a large bowl stir together crushed pineapple, pineapple chunks, sugar, flour, and cheese. Spread mixture into prepared baking dish. Sprinkle crushed crackers over the top, then drizzle with melted butter.
Bake for 20-25 minutes until mixture is bubbly and topping is browned. Allow to sit for 5-10 minutes, top with cracked black pepper and serve.