Preheat oven 350 degrees
Prepare pasta according to the directions drain and transfer pasta into a casserole dish prepared with nonstick spray.
While the pasta is cooking dice the ham and set it aside.
In a sauce pot melt butter and then add flour, dry mustard, garlic powder, onion powder and whisk together for two minutes.
Slowly add milk to saucepan and whisk frequently until smooth. When mixture is smooth and completely free of lumps remove the pot for heat and add in ham and cheese stirring until combined and the cheese it melted.
Pour sauce over the cooked pasta, (give it a stir to make sure the sauce it evenly distributed)
Top with remaining cheese.
Bake at 350 degrees for thirty minutes or until the cheese is bubbly and golden.