Blanch the asparagus for 1 minute. Drain. Trim the woody part from the bottom of each spear, then cut each spear in half crosswise.
Melt the butter in a large skillet over medium heat. Add the asparagus and cook and stir for 1 minute. Season with salt and pepper to taste. Remove from the heat and add the lemon juice. Garnish with the lemon zest.