1. Heat grill to low. Trim larger leaves, and slice heads in half lengthwise. Rinse well under cold water to clean.
2. In a large bowl, whisk together white wine vinegar, chili sauce, brown-sugar and vegetable oil; season with salt and pepper. Add bok choy; toss to coat. Remove from bowl, reserving sauce.
3. Place bok choy, cut sides down on grill; cover, and cook until tender. About 10 minutes. Serve bok choy and top with reserved sauce.

What to Serve with Bok Choy:

Serve it as a side with grilled shrimp or chicken. Add to your next stir-fry dish for a veggie-packed meal.