Grease or oil a 1-1/2 quart casserole. Arrange a layer of cooked macaroni over bottom and add layer of sliced tomatoes. Combine salt, sugar, basil, and flour and sprinkle half of this mixture over tomato layer.
Add more macaroni, more tomatoes, and remaining seasoned mixture. Pour cream over the top, then add crumbs and dot with butter.
Cover casserole and bake in 350F oven for 45 minutes. Uncover the casserole during the last 15 minutes to allow the crumbs to brown lightly on top.