Melt butter and add onion and whole garlic cloves. Saute until onion is golden. Add tomatoes with liquid and simmer over low heat 1 1/2 hours, or until sauce is thick. Add bouillon cubes, season to taste with salt and heat until cubes dissolve. Add chiles and/or bacon, if using, and simmer 30 minutes longer. When ready to serve, remove garlic cloves and chiles. Stir in oil. Meanwhile, cook macaroni until tender but firm and drain. Pour tomato sauce over macaroni and add cheese. Toss with fork and spoon until sauce and cheese are well distributed.