Cook the spaghetti noodles according to package instructions. Set aside.
In a large bowl, combine the egg yolk, heavy cream, Parmesan cheese, basil, and parsley. Whisk and set aside.
Heat the oil in a wide cooking pot or casserole.
Add-in the pancetta. Cook for 5 minutes.
Put-in the garlic and cook until it turns light brown.
Add-in the shredded baked chicken. Stir. Cook for 1 minute.
Put-in the cooked spaghetti noodles. Toss.
Adjust the heat to low and add the heavy cream and egg mixture. Toss until all the ingredients are well distributed.
Season with salt and pepper
Transfer to a serving plate. Garnish with some grated lemon peel on top.