Let the polenta swell with the water and a little salt (see instructions on the package). Stir 2 tablespoons of olive oil into the polenta and smooth out in a gratin dish.
Cut the tomatoes into small pieces and mix with the spices (some oregano, basil). Then spread the tomato pieces on the polenta.
Cut the onion into slices and sauté with a little olive oil. Spread the steamed onion rings on the tomato pieces.
Place the drained corn in a small bowl. Cut the Emmentaler into small pieces and add to the corn. Cut the olives into small slices and add them to the bowl. Add a little pepper, salt, oregano and basil and mix the ingredients well.
Distribute everything evenly on the onion rings and bake in the oven for about 20 minutes.