Bring a large pot of salted water to a boil. Add macaroni and cook for 20 minutes. (Tip: Cooking the pasta this long prevents the noodles from absorbing too much cheese sauce and keeps the dish creamy.) Drain and set aside.

In a large pot over medium heat, melt butter. Whisk in flour, salt, and paprika until smooth.

Gradually add milk, whisking in each addition completely before adding more.

Whisk the sauce for 1–2 minutes until thickened.

In a small bowl, place egg yolk. Add a spoonful of hot milk mixture, whisk to temper, then add back to the pot and whisk in.

Turn heat to low. Tear American cheese into pieces and add to the pot. Add half of the cheddar and all of the Italian blend cheese. Stir until melted and smooth.

Stir to combine and fully melt the cheeses.

Add the drained macaroni to the cheese sauce. Stir gently until everything is combined and coated.

Transfer the macaroni and cheese to a 9×13-inch baking dish. Top with the remaining cheddar cheese.

Place under the broiler until just browned and bubbly on top. Watch closely to prevent burning.

To freeze: Cover the baking dish with plastic wrap, then foil. Freeze for up to 3 months.