Preheat your oven to 400℉. Grab a pie dish or square baking dish.
Place a layer of tomatoes, peppers and drizzle with olive oil and sprinkle on dried oregano generously. Next place half the mozzarella in the dish and then all of the pieces of feta evenly. Top then with the remaining mozzarella slices, tomato, peppers, drizzle olive oil, dried oregano and chili pepper flakes. Bake covered for 20-22 minutes then uncover and broil for a few minutes or until golden brown.