Bring water to a boil, lower the heat and add 1/2 cup of polenta to form a mash. Then add the rest and cook until creamy. Add the butter and thyme and salt and pepper to taste. Place the polenta into a greased pan and bake at 350° for 15 minutes.
Stir-fry the cherry tomatoes, oregano, garlic powder, salt and pepper in a little of the Tonnino olive oil. Serve the polenta on a plate. Top with the tomatoes and Tonnino Tuna in olive oil.