Steps
1. Bring a pot of salted water to a boil and cook the spaghetti until al dente.
2. While pasta cooks, heat a pan over medium heat and add diced pancetta. Cook until crispy.
3. Lightly crush the garlic clove and add it to the pancetta pan for flavor; remove and discard after 1 minute.
4. In a bowl, whisk the egg with grated Parmesan, a pinch of salt, and plenty of black pepper.
5. Drain the spaghetti, reserving a small cup of pasta water.
6. Quickly toss the hot spaghetti into the pan with pancetta off the heat.
7. Remove the pan from heat and immediately mix in the egg and cheese mixture, stirring vigorously to create a creamy sauce without scrambling the egg.
8. Add reserved pasta water little by little if needed to loosen the sauce.
9. Serve immediately with extra Parmesan and black pepper on top.