Bring a large pot of salted water to a boil. Cook spaghetti according to package instructions until al dente. Reserve 1 cup of pasta water before draining.

In a large skillet over medium heat, toast the black pepper for about 1 minute until fragrant.

Add the hot spaghetti directly to the skillet with the toasted pepper. Toss well to coat all strands.

Turn off the heat and gradually mix in half of the reserved pasta water and half of the grated Pecorino Romano cheese, tossing vigorously until creamy. Adjust with more cheese and water as needed.

Serve immediately, topped with additional cheese and pepper if desired.