Step 1

Preheat oven to 350 degrees. Cook pasta 2 minutes less than package directions. Combine grated cheese in a large bowl.

Step 2

In a large saucepan over medium-low heat, melt butter. Whisk in flour 2 to 3 minutes, whisking constantly. This cooks out the flour taste. Slowly whisk in the half and half, in three additions, letting it thicken in between each addition. Once all the half and half has been added cook until very thick. Reduce heat to low.

Step 3

In a small bowl, beat egg. Slowly drizzle in 1/4 cup of the sauce it into beaten egg while whisking egg mixture. Pour egg mixture back into the sauce, stirring constantly until completely incorporated.

Step 4

Add all but 1 1/2 cups of cheese and stir until melted. Season with salt and pepper. Pour cooked macaroni into a large baking dish then pour sauce over the noodles. Stir until combined. Top with remaining cheese and bake for 20 to 25 minutes or until bubbly and golden on top.