This version forgoes the classic canned cream of mushroom soup base ... and 2 cans tuna in a blender; process until smooth, about 25 seconds. Set tonnato sauce aside. Melt butter in a large ...

Green beans and tuna aren't the only two pantry staples that can be transformed into a casserole with the addition of cream of mushroom soup ... under the broiler to melt the cheese (or skip ...