Scalloped Pineapple Casserole

1/2 cup sugar
3 tablespoons self rising flour
1 can pineapple tidbits, juice reserved
3 tablespoons reserved pineapple juice
1 cup sharp cheddar, grated
1/2 cup Ritz cracker crumbs -- (1/2 to 3/4)
1/4 cup melted butter

Mix together sugar, flour, pineapple, juice, cheese. Pour into greased casserole dish and cover with cracker crumbs. Pour melted butter over crumbs. Bake 20 minutes at 300�F.