This is one of my, or could be my favorite recipe. I made it last night and then forgot to take a photo. So the photo is what it looks like the day after, having been left out all night. It looks a lot better when its fresh, when I get around to cooking it again I will update, if I remember to. 
Enjoy!
4 boneless chicken breasts (I always hammer the crap out of my chicken with one of those meat beater things).
1 cup mayo
1 cup sour cream
2 cups parmesan cheese
salt & pepper to taste
2 tsp garlic
Mix the mayo, sour cream, parmesan cheese, salt & pepper and garlic powder together. Put a layer in a 9 x 13 baking dish, add chicken. Cover with swiss cheese and then top with remaining mixture.
Cook at 375 degrees for 60 min. I like to cook it for about 50 min then sprinkle more parmesan on top and crank up the heat to about 425 to get a little crisp on the top. Im not responsible if you try this and burn it.