Fry the bacon until it is crisp. Drain and break it into pieces.

Boil the spaghetti in salted water until al dente. If you like, add some bacon grease to the boiling water.

Drain the spaghetti and return it to the pot. Add the butter, pieces of bacon, parmesan cheese, and pepper and mix it up until the butter is melted.

Add the raw beaten egg and mix it quickly until the spaghetti is coated. Serve immediately.