Crab Dip Casserole

2 cans crabmeat, drained
1 cup mayonnaise, mixed with a little bit of ketchup
1 teaspoon pickle relish
1/2 can cream of mushroom soup
1/3 cup grated cheddar cheese
mushrooms (optional)

Mix crabmeat, mayonnaise and pickle relish. Add soup and mix. Add cheese (hold back a little bit of the cheese to sprinkle on top) and mix well. Bake at 325° for about 60 minutes. Serve hot.