Use spinach fettuccine for an especially attractive dish.
Bring to a rolling boil in a large pot:
Add and cook until tender but firm, 1 to 4 minutes, depending on their thickness:
Scoop out the asparagus with a slotted spoon, transfer to a colander, and rinse under cold water to stop the cooking. Add to the boiling water and cook until tender but firm:
Meanwhile, melt in a large skillet over medium heat:
Add the asparagus and cook, stirring, just to coat with butter, about 1 minute. Stir in and heat through:
Drain the pasta and add it to the skillet along with:
Toss to combine and serve hot.