
Bring a large pot of salted water to a boil. Once water is boiling, add dry noodles and cook about 1 minute less than the package directs for al dente. After cooking, drain.
Preheat oven to 375ºF and melt about 2 tablespoons butter in the bottom of a large casserole dish (about 3 quarts and 9x13") in the preheating oven.
Once butter is melted, remove casserole dish from oven and cover the bottom with one layer of macaroni (half of the macaroni). Then layer with half of the cheddar and muenster and then add a few pats of butter on top. Add the remaining noodles, cheese, and a few more pats of butter. Mix the eggs in the whipping cream and pour it over the entire casserole.
Bake at 375ºF for about 20-25 minutes. When fully cooked, it should be thick and not runny. Mine is typically cooked in 20 minutes. Best when served hot straight out of the oven. Taste and add salt as preferred.