Blanche broccolini in a large pot of salted water for 2 minutes. Drain immediately and immerse in a bowl of ice water. Once cooled, drain and remove as much water as possible with paper towels.

Melt butter in a large sauté pan. Add the lemon zest and garlic and stir. Add broccolini and sauté until just tender. Add lemon juice, salt and pepper. Toss well before serving.