grated cheese – you can change up your mix, but I did 3 oz. (not fresh) mozzarella, 2 oz. cheddar and 1 oz. parmesan
pesto – homemade, ideally
Start by cooking the pasta according to the package directions. While it’s cooking you can prep the cheese and whisk together the egg and milk in a separate bowl.
When the pasta is cooked, drain and return to the pot over medium heat. Stir in the butter until melted. Next, stir in the egg and milk, stirring quickly so the egg does not scramble.
Next, stir in the cheese, about an ounce at a time, so the cheese doesn’t clump up as it melts. When it has totally melted, stir in the pesto. Taste, then season using salt and pepper until you are happy with it. I also added a little bit of Penzey’s Pasta Sprinkle.