Knockwurst can be boiled or steamed but is at its best when lightly grilled and served with good pretzels, yellow or Dijon mustard, and a pale ale; a "hobo pack" of cremini mushrooms and garlic, also cooked on the grill, makes the meal a feast.
Preheat a grill to medium (if you are using a charcoal grill, coals are ready when you can hold your hand 5 inches above grill for just 5 to 6 seconds). Grill knockwurst, turning frequently, until marked by grill and heated through, about 5 minutes. Cut each knockwurst on the diagonal into 1/2-inch slices. Serve with grilled mushrooms and garlic.
The knockwurst will char quickly on the grill; be sure to turn it frequently.