Heat a large skillet over medium-high heat. Once the pan is heated, add the pancetta and cooked until crispy, 5-7 minutes. Using a slotted spoon, transfer the pancetta to a paper towel lined plate.
Let the pan cool (with pancetta fat) for 2-3 minutes and then add the garlic and red pepper flakes and stir for 1 minute or until fragrant. Add the leeks and butternut squash noodles to the pan and season with salt and pepper. Cook until pasta is al dente or softened to your preference, 5-7 minutes. Stir back in the pancetta along with the Parmesan cheese. Divide into bowls and serve.