In a deep skillet or medium pot, egg-poaching liquid to a boil over high heat, then leave on low heat. Set aside.
In a large pot of boiling salted water, cook pasta according to package instructions; reserve 1/2 cup water and drain well.
Heat a large skillet over medium-high heat. Add bacon and cook until brown and crispy, about 5-8 minutes; reserve excess fat.
add the onion, and cooking until the bacon is crispy and the onion is translucent.
Stir in garlic until fragrant, about 1/2 minute. Reduce heat to low.
stir in pasta and Parmigiano Reggiano cheese, and gently toss to combine; season with salt and pepper, to taste. Add reserved pasta water, one tablespoon at a time, until desired consistency is reached.
Evenly divide pasta between 3 warm bowls. Place each egg atop each bowl of pasta.
mixing up the pasta to spread the egg and yolk throughout the bowl.
Top generously with grated Parmigiano Reggiano cheese. Serve immediately, garnished with parsley.