There are a couple of different legends of how macaroni and cheese became a popular dish in America. One ties the origin to a New England church supper where it was known as macaroni pudding. Another tale ties the origin to Thomas Jefferson bringing the recipe back to America after a trip to Italy. Either way, macaroni and cheese has become a staple main and side dish of American cuisine. Due to the salt content in many cheeses, the final dish often turns out too salty. If so, a simple fix reducse the sodium level to a more palatable taste.
Keep the macaroni and cheese warm. Place the macaroni and cheese in the oven on a low temperature, such as 125 degrees F, or keep the macaroni and cheese on the stove on the lowest setting.
Boil water in a pot. Fill the pot two thirds full with water and bring to a boil over high heat.
Pour one quarter to one half the amount of pasta you used in the original dish into the pot. If the macaroni and cheese is lightly salty, use the smaller amount. If the pasta is extremely salty, use the greater amount. Do not add any additional salt to the water, even if instructed on the packaging.
Cook the pasta until al dente as directed on the pasta box. Different types of pasta have different cooking times.
Remove the pasta from the stove and strain in a pasta strainer.
Add the newly cooked pasta to the macaroni and cheese and stir until well mixed. By keeping the original dish of macaroni and cheese hot, the cheese will not have hardened. Therefore, the new pasta will soak up some of the cheese sauce and therefore salt, lowering the overall content in the entire dish.
If you need more "cheese sauce" for your macaroni and cheese because of the amount of pasta you have added, stir in a little cream when adding the new pasta. This will thin the cheese sauce allowing it to spread around amongst the pasta. Stir until well mixed.