For the polenta cakes, bring the polenta to a boil with the soup in a pot and let it swell until all the liquid has evaporated. Remove from heat and season with salt and pepper.
Brush a muffin tray with oil and fill the muffin cups 2/3 full. Wash and slice the tomatoes and spread them on the polenta. Spread the grated cheese on top as well.
Bake at 190 °C top and bottom heat for 15 minutes.
You can also season the polenta cakes with paprika powder or curry, for example.