1. Heat the grill. Combine the olive oil, vinegar, cheese, garlic, and black pepper in a food processor or blender and puree to make a smooth dressing. Transfer to a bowl, stir in the basil, and set aside.

2. Fill a large pot with ice and water. Bring a large pot of salted water to a boil, add the asparagus, and cook for about 3 minutes, until just tender. Drain and plunge the asparagus into the ice water to stop cooking; then drain again. Rub the asparagus with 1 tablespoon of olive oil, sprinkle with salt and pepper to taste, and grill over a medium-hot fire, turning frequently, for 3 to 5 minutes, or until well seared.

3. In a medium bowl, combine the arugula, beans, and onion. Stir the dressing well and pour just enough onto the arugula-bean mixture to moisten the ingredients. (You will probably have some dressing left over; cover it and refrigerate to keep it for up to a week.) Toss well, place the salad on a serving platter or individual plates, top with the pancetta and asparagus, and serve.