Bring a large pot or Dutch oven filled with water to a boil. Add in a generous amount of salt and stir.
Stir in the pasta and, 2 minutes before it is al dente, reserve 1 cup of the pasta water.
8 ounces dry fusilli pasta
Drain the pasta and set aside.
In a large sauté pan, melt the butter over medium heat. Add in the pepper and cook until fragrant and toasted, about 1 minute.
3 tablespoons unsalted butter, 1 teaspoon freshly ground black pepper
Add in ½ cup of the pasta water and bring to a boil. Add in the pasta and toss to coat.
Turn the heat down to low and add in the cheeses. Toss the pasta continually until the cheese is melted. If the mixture seems too thick, add in more pasta water, a little at a time to thin.
¾ cup freshly grated Parmesan cheese, ½ cup freshly grated Pecorino Romano cheese
Serve topped generously with more cheese and pepper, if desired.