Bring a stock pot of lightly salted water to a boil. Add a little bit of salt to the water - about 2 tsp or so.
In a mixing bowl, whisk together the eggs, yolk, Parmesan and fresh cracked black pepper to taste. Set the bowl aside.
Heat a large skillet on high heat. Add pancetta (or the sub of your choice) to the pan and cook until the fat renders and the meat is lightly crisp. Keep the pancetta in the pan and remove the pan from the heat.
Add the spaghetti to the boiling water and cook until just before al dente, 1-2 minutes before the box instructions.
Transfer the pasta to the pan with pancetta/pancetta fat. Pour the egg mixture into the pan and quickly toss everything together, using a rubber spatula or a utensil that will delicately handle the pasta. If you want the sauce to be more "saucy" and less glossy/sticky, add a little bit of pasta water to the pan and toss with your pasta. If you want the sauce to be stickier, turn the heat on low and continue tossing the pasta in the sauce until it adheres to the pasta.
Serve immediately and top with a fresh grating of Parmesan cheese and a fresh crack of black pepper.