Put a large pot of water on to boil for the spaghetti. Cook the spaghetti to al dente according to instructions and while you're waiting for the water to boil and the spaghetti to cook, continue with the recipe instructions.

In a small bowl, beat the eggs to even consistency and mix in the cheese (a fork works well). Set aside.

In a large, heavy pan over medium heat, brown the guanciale (or pancetta/bacon) until crisp, about 6-8 minutes.

Lower the heat to low. Carefully remove all but about two tablespoons of the drippings from the pan. Scoot the guanciale to the side and add the garlic to the drippings and let it bloom for about 30 seconds.

If the pasta isn't ready, remove the guanciale and garlic mix from the heat.

When the pasta is ready, turn off the heat on the water and use tongs or a spaghetti lifter to remove the spaghetti from the water and into the pan with the guanciale, letting it drain back into the pasta pan just a little. Continue until all the hot pasta is transferred.

Turn the heat on the guanciale pan to just a bit higher than the lowest setting. Use the tongs or spaghetti lifter to evenly mix the pasta and guanciale.

Give the egg and cheese mixture a good stir and add it to the pasta mixture all at once. Toss until evenly combined throughout the spaghetti. If your spaghetti looks dry, add some of the pasta water a very small amount at a time. Remember, you're not making a sauce, just using the water to help distribute the egg and cheese and to give the pasta a slight glisten.

Serve immediately in a large bowl to pass around the table or in individual bowls. Garnish with more grated Pecorino Romano cheese and chopped parsley, and enjoy.