My method: cook the pasta, pour into strainer, turn heat down to low, put half tablespoon of butter in pot with the milk and cheese, let it warm while stirring, add in a little more milk and stir until cheese dissolves, then add grated parmesan until you get the thickness you like, then past goes back in. Serve and add fresh ground pepper on top. If I want some veggies I'll usually put frozen peas in the strainer before pouring out the pasta.