Bring a pot of salted water to a boil and cook the whole wheat spaghetti according to package directions until al dente.
Reserve 0.25 cup of the starchy pasta water before draining the noodles.
While the pasta cooks, place the diced pancetta in a large skillet over medium heat and cook until crispy and the fat has rendered.
Add the minced garlic to the skillet with the pancetta and sauté for 30 seconds until fragrant, then turn the heat to low.
In a small bowl, whisk together the whole egg, liquid egg whites, grated parmesan, and cracked black pepper until well combined.
Add the drained pasta to the skillet with the pancetta, tossing to coat the noodles in the rendered fat.
Remove the skillet from the heat entirely to prevent the eggs from scrambling.
Slowly pour the egg mixture over the pasta while tossing continuously with tongs, adding the reserved pasta water a tablespoon at a time until a smooth, creamy sauce forms.
Serve immediately with an extra sprinkle of black pepper if desired.