Bring a large pot of salted water to a boil and cook the whole wheat spaghetti until al dente according to package directions.
Reserve 0.25 cup of the starchy pasta cooking water before draining the noodles.
In a large skillet over medium heat, cook the diced pancetta until the fat has rendered and it becomes crispy.
Add the diced chicken breast to the skillet with the pancetta and sauté until the chicken is cooked through and golden brown.
Stir in the minced garlic and cook for 1 minute until fragrant, then reduce the heat to low.
In a small bowl, whisk together the egg yolks and grated parmesan cheese until well combined.
Add the cooked spaghetti to the skillet, tossing it with the chicken and pancetta to coat in the rendered fats.
Remove the skillet from the heat entirely and slowly pour in the egg mixture while continuously tossing the pasta.
Gradually add the reserved pasta water one tablespoon at a time while tossing until a silky, creamy sauce forms.
Season the dish with sea salt and freshly cracked black pepper before serving immediately.