In a skillet cook sausage and onions over medium high heat until sausage is done with no pink remaining. Break up with a wooden spoon as it cooks so the sausage crumbles. Drain fat.

Add remaining ingredients except for cheeses. Bring to a boil, then turn heat to medium low. Cover and cook until pasta is tender, about 10 minutes, stirring occasionally.

When pasta is done, remove from heat. Sprinkle with cheeses and let sit about 5 minutes so cheese can melt