To make pineapple casserole, first, preheat the oven to 350°F. Take a 2-quart baking dish and spray it with non-stick cooking spray. Meanwhile, drain the canned pineapples very well and reserve 6 tablespoons of the juice for the recipe
Now, take a large bowl and in it add 6 tablespoons of pineapple juice, flour, brown sugar, and stir them well. To this, add the pineapple chunks and mix well. Once done, pour all of this into the baking dish and sprinkle grated cheddar cheese over it.
Take a medium bowl and add the melted butter to the crushed cracker crumbs. Stir it vigorously till it is properly coated in butter. Now, sprinkle over some cheese on it and bake it for about 30 minutes. Then, allow the casserole to be for 10 minutes or so till it thickens. Once done, serve warm.