Cut the squash in half lengthwise using a serrated knife. Scoop out and discard the seeds with a spoon. Put the squash onto a microwave safe plate, cover tightly with plastic wrap and microwave on high for 13-14 minutes, until tender and the flesh can easily be detached with a fork.Use a fork to scrape the inside of the squash into spaghetti-like strands and place into a bowl.
In a separate bowl, mix together the parmesan cheese, egg yolks, salt and pepper and set aside.
Cook the pancetta in a large skillet over medium-high heat, stirring occasionally, for about 7-8 minutes, until crisp. Add the garlic and red pepper flakes to the skillet and cook, stirring for about 1 minute, until the garlic is fragrant. Stir in the heavy cream, scraping up any brown bits in the pan, and bring to a simmer. Reduce the heat to medium-low and add the squash strands. Toss together until squash is coated.
Add the parmesan and egg mixture slowly and toss to gently cook the eggs and make a creamy sauce. Turn off the heat and stir in the parsley. Divide among 4 plates and serve with more Parmesan and parsley for garnish if desired.
* Percent Daily Values are based on a 2,000 calorie diet. Your daily value may be higher or lower depending on your calorie needs.