Cook the spaghetti according to the directions. When the pasta is al dente, save the pasta water.
While the spaghetti is cooking, cook the bacon crispy. When the bacon is done, remove it from the pan, and pour out most of the grease, leaving about a tablespoon in the pan.
In the same pan, saute the garlic.
In a bowl, add the eggs and whisk with a fork.
Add the pasta to the sauteed garlic. Add the bacon back in.
Add the eggs. Stir the eggs into the pasta quickly, being sure they do not scramble. You want the eggs to cook, and coat the pasta, but not to scramble. As the dish start to cook, remove the pan from the heat. The heat from the pan and the pasta will continue to cook the eggs.
Add the cheese and continue to stir. If the pasta is a bit too dry, add some of the pasta water in. Top with parsley.