Using a cast-iron skillet (or a non-stick skillet), cook the meat, onions, and bell peppers until meat is brown and veggies are cooked through. Add salt and pepper to taste
Add diced potatoes and cook with the lid on, for about 15 minutes on low-med heat stirring occasionally
If you are using a cast-iron skillet, add the milk and the cornstarch to the pan and stir. If you are using a casserole dish, transfer meat and potatoes to the dish and add a mixture of milk and cornstarch. Place the Provolone cheese rounds on top of the meat and bake in a 350F oven for 15 to 20 mins or until cheese is melted and bubbly.