Step 1

Whisk tamarind sauce, garlic, ginger and garam masala in a 9-inch baking dish. Add chicken and turn to coat. Marinate at room temperature, turning once, for 30 minutes.

Step 2

Preheat grill to medium-high.

Step 3

Remove the chicken from the marinade (discard the marinade). Oil the grill rack. Grill the chicken, turning once halfway, until an instant-read thermometer inserted in the thickest part reaches 160 degrees F, 6 to 10 minutes. Let rest for 5 minutes. Sprinkle with scallions and serve with more sauce, if desired.