Boil noodles for 1 minute and 30 seconds and drain, reserving 2 cups of pasta water.
Melt butter in a saucepan over medium heat, then add 1½ cups of reserved pasta water. Raise heat, then bring to a boil.
Add the noodles and let them cook for 1 minute.
While stirring continuously, begin adding parmesan cheese, about 1 tablespoon at a time, allowing it to emulsify into the liquid. If the liquid disappears entirely, slowly add additional ½ cup of pasta water until it returns to a liquid consistency.
When all the cheese is added, remove from heat then stir in 3 tablespoons of heavy cream and 2 tablespoons of Momofuku Garlic Crunch, then season with Kosher salt to taste.
Serve, topping with more Garlic Crunch.
