1. In a large pot of salted boiling water, cook pasta according to package directions until al dente. drain, reserving 1/2 cup pasta water, and return to pot.
2. Meanwhile, in a large skillet over medium heat, cook bacon 5 minutes. add garlic and cook until bacon is crispy, 2 to 3 minutes more. transfer to a bowl and drain half the fat in skillet.
3. Add chicken to skillet and increase heat to medium-high. season generously with salt and pepper and cook, flipping halfway through, until no longer pink, 10 minutes.
4. Reduce heat to low and return bacon to skillet. toss, then add cooked pasta and toss until combined.
5. In a small bowl, beat together eggs, parmesan, and parsley and season with salt and pepper.
6. Pour egg mixture over pasta and toss until coated, then add a couple tablespoons pasta water until creamy. (add more pasta water by the tablespoonful as necessary.)
7. Garnish with parmesan and parsley and serve immediately.