In a medium bowl, whisk egg yolks, egg, and Parmesan until completely smooth. Set aside for a moment.
In a Dutch oven or large skillet over medium heat, cook diced bacon until crispy, stirring occasionally. Add garlic and sauté 1 additional minute until fragrant. Drain grease from pan and discard.
Bring a pot of salted water to a boil and cook pasta until just barely al-dente. Reserve 1-1/2 cups pasta cooking water and drain pasta.
Add pasta and 1/2 cup reserved pasta water to bacon mixture. Cook over medium heat 2-3 minutes until liquid is absorbed. Remove from heat and allow to cool 2 minutes.
Whisk 1/4 cup pasta water into egg yolks until smooth. Fold egg sauce into hot pasta mixture, stirring constantly with a wooden spoon until a creamy sauce forms and coats pasta. (drizzle in additional pasta water if needed to loosen sauce)
Stir parsley into carbonara and season with salt and pepper to taste. Serve carbonara immediately while hot with additional Parmesan grated on top. Enjoy!