- 1 pound spaghetti
- Kosher salt
- 4 tablespoons extra-virgin olive oil, divided
- 1 1/ 2 teaspoons freshly cracked black pepper
- 3 tablespoons unsalted butter
- 1 lemon, zested and juiced
- 1/ 4 teaspoon chili flakes
- 1 cup grated Pecorino Romano
- 1/ 2 cup grated Parmesan
Bring a large pot of salted water to a boil and cook spaghetti until al dente.
Meanwhile, heat 3 tablespoons olive oil and black pepper in a skillet over medium-low heat until fragrant and black pepper is barely starting to sizzle, about 1 minute. You don’t want the oil to be too hot because you want to slowly infuse the pepper into the oil.
Drain the pasta, reserving 1 cup pasta water. Increase flame under the skillet to medium, and stir the butter, lemon zest and juice, and chili flakes into the oil. Add the pasta, using tongs to mix in.
Add both cheeses, remaining 1 tablespoon olive oil and 1/2 cup pasta water to the skillet and stir until cheese is completely melted. Add a few more tablespoons pasta water to adjust consistency. Season to taste with salt and black pepper.
Serve immediately with Parmesan.