Cook spaghetti according to package instructions. Reserve 1/2 cup of pasta water before draining.
In a large skillet, cook bacon over medium heat until crispy. Remove and set aside.
In the same skillet, add diced chicken and cook until golden and fully cooked. Remove and set aside.
Reduce heat to low. Add garlic and sauté until fragrant.
In a bowl, whisk together egg yolks, heavy cream, Parmesan cheese, and reserved pasta water.
Add cooked pasta to the skillet, then pour in the egg mixture, tossing quickly to coat evenly.
Return bacon and chicken to the skillet, stirring to combine.
Season with salt and black pepper to taste.
Garnish with fresh parsley and serve immediately.