How to Make It
Heat a large skillet over moderately high heat. Add the pancetta and cook, stirring occasionally, until crisp, 3 to 5 minutes. Drain off the excess fat, leaving just enough to coat the skillet. Add the asparagus and 2 tablespoons of water and cook over moderately high heat until the asparagus is crisp-tender, 2 to 4 minutes. Remove the skillet from the heat and immediately add the egg yolks and butter to the skillet. Cook, tossing, until the butter is melted. Toss in the Parmigiano-Reggiano and season with salt and the pepper. Transfer to a bowl and serve right away.