Use the adverb zestily for anything that's done in a spirited, energetic way. When a marching band performs zestily, the whole crowd shares in their enthusiasm.
Doing something zestily can mean tackling it with enthusiasm: "He scrubbed the bathtub zestily, and soon it was gleaming." You can also use this word for things that have a strong flavor, whether they're spicy, tart, or pungent: "They seasoned the stir fry so zestily that I asked for a big glass of milk to drink." Zestily comes from the French zeste, "orange or lemon peel used as flavoring."