Kosher salt and freshly ground black pepper
1 cup grated Parmesan, plus more for serving, optional
3 large egg yolks
1 pound jumbo asparagus
8 ounces fettuccine
6 slices thick-cut bacon, cut into 1/2-inch pieces
1/4 teaspoon crushed red pepper flakes
1 clove garlic, minced
1/4 cup fresh parsley leaves, chopped