Step 2

Bring a large pot of salted water to a boil. Add the spaghetti and cook until just al dente, 8 to 10 minutes.

Step 3

While the pasta cooks, mash the soft butter with the olive oil and Pecorino in a large bowl to form a paste.

Step 4

When the pasta is cooked, reserve ½ cup of the pasta cooking water and drain the spaghetti. Add the spaghetti directly to the bowl with the butter mixture. Toss well to coat, adding the pasta water as needed to make a thick, creamy sauce that coats the pasta strands. Season to taste with salt and lots of freshly ground black pepper. Divide the pasta among four plates; serve immediately.