Bring a large pot of salted water to a boil and cook the whole wheat spaghetti according to package directions until al dente.
While the pasta cooks, dice the chicken breast into small bite-sized pieces and finely mince the garlic.
In a large skillet over medium heat, sauté the diced pancetta until the fat renders and the meat becomes crispy.
Add the diced chicken breast to the skillet with the pancetta and cook until golden brown and cooked through, approximately 5-6 minutes.
In a small bowl, whisk together the whole egg, egg whites, and grated parmesan cheese until well combined.
Reserve 0.25 cup of the starchy pasta water, then drain the spaghetti.
Turn off the heat under the skillet and add the minced garlic, stirring for 30 seconds until fragrant.
Add the hot pasta to the skillet with the chicken and pancetta, tossing to combine the ingredients.
Slowly pour the egg and cheese mixture over the pasta while tossing constantly; the residual heat will create a creamy sauce without scrambling the eggs.
Thin the sauce with a splash of reserved pasta water if needed, then season with sea salt and black pepper and garnish with fresh parsley.