Preheat 350 degrees F.
In a 9-inch Dutch oven melt the butter and cook the onions and peppers until tender. Add the minced garlic and heat until fragrant.
In a small bowl mix milk, spices, cornstarch, bouillon, and add to the Dutch oven. Heat until bubbly. Salt and pepper to taste.
Stir in the cheese allowing it melt.
Toss the chicken and spaghetti into the veggies and sauce.
Bake for 30-40 minutes until warmed through.
Remove and allow to rest for 10 minutes.
Serve.