Heat a dutch oven or large heavy bottomed pot over MED heat and add butter and oil. Add diced chicken and cook for 3-4 minutes, until golden brown. Chicken may not be cooked all the way through, and that's okay. Remove chicken to a plate.
Add diced onion and ham to the pot and cook about 3 minutes. Return chicken to pot and add garlic powder, minced onion, dried parsley, dijon mustard, salt and pepper, stirring to combine.
Add chicken stock and stir. Turn heat up to HIGH and bring to a boil. Once boiling, add pasta, reduce heat to LOW, cover, and simmer 10-15 minutes, stirring frequently, until most of the liquid is absorbed and pasta is cooked.
Stir in heavy cream and 1 cup of shredded cheese. Sprinkle the top of the dish with remaining cheese and broil on HIGH for 1-2 minutes, or until cheese is melted and bubbly.
Serve garnished with parsley if desired.