Cover dish with foil and bake for 30 minutes. (This is where the potato effects the dish. If you use the potato, I'd increase baking time to 45 mins. If you don't add potato, keep it at 30 minutes.) Remove foil and add shredded cheese. Return to oven for another 15 - 20 minutes or until the cheese is golden brown. (I have had no luck with this so thinking about broiling for a minute or so next time.)