- Heat grill to medium.
- While the grill heats, make the gastrique (It can also be made ahead and refrigerated): combine vinegar, sugar, water, 1/4 teaspoon salt and rhubarb in a non-reactive saucepan and simmer until thick and jam-like, 10 - 15 minutes. Set aside.
- Brush chicken pieces with oil, and salt and pepper generously. Put chicken on grill, skin side down, for about 5 - 6 minutes. Be prepared for flare-ups as the fat cooks out of the skin; move meat around as needed to keep it from getting burned. Turn to cook the other side for about 5 minutes, then continue grilling, turning as needed to prevent burning, until the chicken is done (no red shows when you make a small deep cut, or 165 on an instant-read thermometer).
- Brush generously with gastrique, and cook for another minute or two on each side, watching closely to prevent burning.
- Serve hot, passing remaining gastrique to add as desired.
|Container: grill, saucepan|
|-||1/2 cup vinegar|
|-||1/2 cup water|
|-||1 cup sugar|
|-||3 cups chopped rhubarb|
|-||4 chicken leg-and-thigh pieces (separate, if preferred)|
|-||2 tablespoons oil, or as needed|
|-|| salt and pepper|