Preheat oven to 375 deg. Grease an 8x8 baking dish.
Cut the chicken into 1/2" pieces, and the ham into 1/2" strips. Pat both dry, and add the ham into the baking dish.
Cook the chicken in a large pan over medium heat until cooked throughout. Use a slotted spoon to transfer only the chicken to the backing dish, leaving any liquid behind.
In a small saucepan, mix all mustard sauce ingredients. Stir together over medium heat. Once it starts to simmer, turn off heat.
Add peas, Swiss cheese, and sauce into baking dish. Stir everything in the dish together until well mixed.
Top with cheddar cheese, and sprinkle with Parmesan.
Bake at 375 until heated through and starting to brown on top, about 30 min. Let cool 10 min before cutting and serving.