Now, take a bowl and prepare the carbonara cream with one egg and one yolk, adding pecorino cheese and freshly ground pepper. Mix well with a whisk.
Meanwhile, cook the spaghetti in a pot with lightly salted water and drain it three minutes before it's done (the cooking time is indicated on the package.). Put the al dente pasta into the pan with the guanciale fat, keeping the heat low, and mix well to combine. Pour in the egg and pecorino cream.