Preheat the grill to medium-high heat. Wash and trim the asparagus spears. In a small bowl, whisk together olive oil, minced garlic, lemon juice, salt, and pepper. Brush the asparagus with the mixture. Grill for 5-7 minutes, turning occasionally, until tender and lightly charred. Remove from the grill and sprinkle with lemon zest. Serve hot.
