The first step is to measure out the milk and butter before you begin. The quantity depends depend on how much pasta you're preparing, but Kraft suggests using 1/4 cup of milk and 4 tablespoons of butter for one box.

Put the dry pasta in a pot and add just enough water to cover the noodles. Butter should then be added, then the box's supplied cheese powder packets. Save the milk addition for later. Before putting the saucepan on the heat, thoroughly whisk the pasta, water, cheese, and butter.

The pasta mixture should be heated on the burner at medium heat with periodic stirring until the water comes to a rolling boil. Reduce the heat to low, toss the spaghetti occasionally, and allow it to boil softly. Don't put a lid on the pot. As the ingredients boil together, you'll notice the cheese sauce thickening and the noodles softening—this is precisely what you want. The majority of the liquid should evaporate in just a few minutes.

Add the milk when there is minimal liquid left in the pot after the cheese sauce has thickened. You want the macaroni to be just simmering as you mix it in, so keep the heat low. Keep an eye on it as you mix to prevent the sauce from becoming overly thick and sticky. Turn off the heat and serve as soon as the consistency is to your liking.