In a medium skillet, heat your oil. Add in the peppers and onions and saute for a few minutes on medium low. Next add in your tomatoes and break them down with your spatula for about a minute or two. Next stir in the garlic for 30 seconds. Now toss in the feta, mozzarella, oregano and chili flakes. Mix everything to combine and melt the cheeses. Transfer to a bowl and serve with warm crusty bread, chips or vegetable sticks.