Pour prepared tomato and cheddar soups into separate saucepans and heat through; ladle some of each into a heatproof mug. Simultaneously pour the soups into a bowl from opposite sides. Use a spoon to create a swirl pattern where the soups meet.
If you wish, top with homemade croutons: Slice white bread into 1/2-inch cubes and add to a preheated greased skillet. Toast over low heat, stirring occasionally, until golden-brown on all sides; season with salt. Add to the soup before serving.