Preheat oven to 350 F
Cook pasta according to package instructions - drain and put back into pot
Stir in sausage, soup, sauerkraut, milk, mustard and garlic
Pour pasta mixture into greased cast iron skillet or casserole dish
Layer 1/2 package of swiss cheese on top of pasta
Bake uncovered for 40-45 minutes
Remove from oven and garnish with chopped green onion
Serve with fresh garlic bread and enjoy!