With the heat on low, add the American cheese, ½ cup at a time, and stir using an 8 figure motion until mostly melted before adding the next ½ cup. Repeat with the remaining cheeses.
Pour the cooked macaroni into the cheese sauce and stir until fully coated. If the cheese sauce is too dry, add in the reserved pasta water ¼ cup at a time until the desired consistency is reached. Serve immediately.
*I liked using the large elbows because there's that much more sauce in each bite, but feel free to use regular elbows!
**About 30 to 60 seconds in the microwave.
***Like Kraft Singles, found in the refrigerated section. DO NOT USE Velveeta.