Heat oil in a large frying pan over medium heat. Add pancetta and cook, stirring often, until it is well browned and most of the fat has been rendered. Remove from heat and set aside.
Bring a large pot of salted water to a boil. Meanwhile, beat together eggs and yolks in a small bowl. Add cheeses to egg mixture and continue to beat until well combined.
Cook pasta. When it's al dente, drain and reserve about 1/2 cup of the pasta water.
Immediately return hot pasta to the pot and stir in egg-cheese mixture, reserved pancetta and pan drippings, and just enough pasta water to make the mixture creamy, about 1/4 to 1/2 cup. Toss with peas. Add pepper if desired.
