Heat the butter in a large skillet over medium-high heat.
Add the mushrooms in an even layer and sprinkle with the lemon zest.
Cook, undisturbed, until browned, about 2 minutes.
Toss with ¼ teaspoon salt and ¾ teaspoon pepper and continue to cook until the mushrooms are tender but not mushy, 4 to 5 minutes.
Add additional salt and pepper to taste.
Transfer to a serving dish and sprinkle with the chives.
Serve warm.
