Prepare pasta according to package directions. Drain. Set aside.
Position a rack in the center of the oven.
Preheat oven to 350°F.
Butter a deep, 4-quart casserole.
Place butter in a medium saucepan. Place pan over medium heat.
When butter has melted and is hot (do not burn), whisk in the flour.
Gradually whisk in the milk. Bring to a simmer, stirring constantly, until the sauce thickens. Reduce the heat to low and simmer 5 minutes.
Remove from the heat and stir in 1 cup Cheddar cheese and 1 cup American cheese. Taste. Add salt, pepper and hot sauce, to taste.
Combine the remaining cheddar and American cheeses.
Spread 1/3 of the cooked pasta over the bottom of the casserole dish.
Top with 1/2 of the shredded Cheddar and American cheese mixture.
Top that with 1/3 of the cheese sauce.
Repeat, using another 1/3 of the pasta with the remaining cheese and 1/2 of the sauce.
Finish with the remaining pasta and sauce.
Sprinkle Parmesan cheese over the top.
Bake until bubbly and golden brown over the edges, about 30 minutes.
Serve hot.