Bring a large pot of salted water to a boil and cook Rigatoni (1 pound) according to package directions. Drain the pasta and set aside.
Preheat oven to 400 degrees F (200 degrees C).
Then, place a large heavy bottomed skillet over medium heat. Then, add Salted Butter (4 tablespoon) let it bubble up before adding Garlic Powder (1 teaspoon).
Then add All-Purpose Flour (4 tablespoon). Use a metal whisk to stir the butter/flour continuously for about 4 minutes until the mixture is nicely browned and has a nutty smell.
Then, slowly pour in Whole Milk (4 cup), whisking constantly. When you've added all of the milk, turn the heat to low and allow the mixture to thicken, stirring frequently with a wooden spoon. You're looking for the mixture to coat the back of the wooden spoon. This is your bechamel sauce.
Next, whisk together one whole Egg (2) and one egg yolk in a heat proof bowl. Then, slowly add one ladle full of the milk to the egg, stirring constantly to temper the eggs.
Next, slowly pour the eggs into the pot with the rest of the bechamel. Stir together over low heat for about 2 minutes. Then, remove the pot from the heat and stir in 3 cup of Extra Sharp Cheddar Cheese (1.5 pound). Season to taste with Salt and Pepper (1 dash).
Next, it's time to add the pasta to the cheese sauce; just fold all of the pasta into the sauce. Then, grease a 9x11 in baking dish and layer 1/3 of the pasta to the dish and top with 1/3 of the remaining cheese. Repeat this process two more times making sure to end with cheese!
Cover with foil and place your mac and cheese in the oven and bake at 400 degrees F (200 degrees C) for 10 minutes. Then, remove the foil and bake for 10 more minutes.
If you'd like an extra bubbly top, you can turn the oven to broil and bake for an additional 2 minutes.
Remove the mac and cheese from the oven and let it rest/cool for at least 10 minutes before serving!