Step 1

Whisk egg yolks, egg, Parmesan, and pecorino Romano together in a small bowl. Reserve at room temperature.

Step 2

Cook pancetta in a skillet over medium, stirring occasionally, until crisp, about 6 minutes. Using a slotted spoon, transfer to a plate lined with paper towels. Reserve drippings.

Step 3

Cook pasta in a pot to al dente according to package instruction. Reserve 1 cup of the cooking water. Place a strainer in a large metal bowl. Pour pasta and remaining cooking water into strainer, letting strainer with pasta stand in water, and allowing the metal bowl to heat, about 1 minute. Remove strainer with pasta, and pour cooking water back into pot. Transfer pasta from strainer to the warm metal bowl.

Step 4

Place metal bowl of pasta on top of pot to keep warm. Stir in egg and cheese mixture, and stir constantly, adding reserved cooking water, as needed, to create a creamy sauce, about 2 minutes. Drizzle in reserved drippings, and stir to combine. Divide pasta between 2 bowls. Top with black pepper and pancetta; garnish with cheese.