Boil salted water in a large pot and cook the spaghetti according to package instructions until al dente.

While the pasta cooks, toast the freshly cracked black peppercorns in a dry pan until fragrant, then remove a small amount for garnish and set aside.

Gradually add some of the hot pasta water to the remaining toasted peppercorns in the pan and bring to a simmer. Meanwhile, in a separate bowl, combine the finely grated Pecorino Romano with a small amount of pasta water to create a creamy paste.

Drain the cooked spaghetti, reserving a cup of the pasta water, and immediately transfer it to the pan with the peppercorn-infused water.

Quickly add the Pecorino paste to the pasta, tossing vigorously to coat evenly, and add more reserved pasta water as needed to achieve a smooth, emulsified sauce.

Serve the Cacio e Pepe immediately, garnished with the reserved cracked black pepper.