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, place the diced pancetta in a large skillet over medium heat and sauté until crisp and golden.
Add the minced garlic to the skillet with the pancetta and cook for 30 seconds until fragrant, then turn the heat to low.
In a small bowl, whisk together the whole egg, egg whites, grated parmesan cheese, and cracked black pepper until well combined.
One minute before the pasta is finished, add the spiralized zucchini to the boiling water to lightly soften.
Reserve 0.25 cup of the pasta cooking water, then drain the spaghetti and zucchini and add them directly to the skillet with the pancetta.
Remove the skillet from the heat entirely; slowly pour in the egg mixture while tossing the pasta constantly to create a silky, creamy sauce without scrambling the eggs.
If the sauce is too thick, add a splash of the reserved pasta water and season with sea salt before serving immediately.