Grilling the asparagus creates robust flavor, which stands up well to the earthiness of truffle oil and the peppery bite of arugula. Both the cooking method and the quality of the ingredients create a stellar first course.
Prepare grill to medium-high heat.
Place asparagus on a jelly-roll pan. Coat asparagus with cooking spray, and sprinkle with salt; toss gently to coat. Place asparagus on grill rack; grill 3 minutes or until crisp-tender, turning occasionally. Remove asparagus from grill; cut into 2-inch pieces.
Combine rind, juice, oil, and pepper in a large bowl, stirring with a whisk. Add asparagus and arugula; toss gently. Divide asparagus mixture evenly among 4 salad plates. Top each serving with 1 tablespoon cheese.