4 oz tamarind concentrate
2 oz boiling water
1/4 cup dry white wine
A few drops of hot pepper sauce (if you like your food on the hot side, add a few more drops)
1 packet artificial sweetener, or 1 tsp honey or agave nectar (optional)
2 tsp kosher salt
10-12 sprigs of flat-leaf parsley
4 scallions (whole)
10 boneless, skinless chicken thighs, trimmed
In a large mixing bowl, dissolve the tamarind concentrate in the boiling water. Stir in the wine, hot sauce, sweetener and salt. Fold the parsley and scallions in half and, using kitchen twine, tie them together (to make a bouquet garni). Add that to the mixing bowl. Add the chicken, and toss well to coat. Cover the bowl with plastic wrap (or transfer all to a ziploc bag), and refrigerate, turning the chicken occasionally, for at least 2 hours, and preferably overnight.
Heat your grill to high. While the grill is heating, remove chicken from the refrigerator. Dry the chicken pieces with a paper towel, and set aside. Remove and discard the bouquet garni. Pour the remaining marinade into a small pot, and set heat to high. Boil the marinade for a few minutes until it is slightly thickened.
Place the chicken on the grill, and brush the top with marinade. Cook for 5 minutes. Turn the chicken, brush with marinade, and cook for 3-4 minutes.
Serve hot, at room temperature, or cold.