Directions:

8 skinless, boneless chicken thighs (about 2 1/2 pounds)
Juice of 1 lemon
Kosher salt
1/2 cup plus 2 tablespoons plain yogurt
1 tablespoon vegetable oil
1/2 small red onion, roughly chopped
3 cloves garlic, smashed

1 2 -inch piece ginger, peeled and roughly chopped
4 teaspoons tomato paste
2 teaspoons ground coriander
1 1/2 teaspoons ground cumin
1 3/4 teaspoons hot paprika
2 tablespoons chopped fresh cilantro
Cooked rice, for serving (optional)

Preheat the broiler. Make shallow cuts in the chicken thighs with a sharp knife. Toss the chicken with the lemon juice and 1 1/2 teaspoons salt in a large bowl.
Pulse 2 tablespoons yogurt, the vegetable oil, onion, garlic, ginger, tomato paste, coriander, cumin, 11/2 teaspoons paprika and 1/2 teaspoon salt in a food processor to make a paste. Toss the chicken in the mixture and let marinate 15 minutes.
Place the chicken on a foil-lined broiler pan. Broil, turning once, until slightly charred and a thermometer inserted into the center registers 165 degrees F, 5 to 6 minutes per side.
Meanwhile, combine the remaining 1/2 cup yogurt and 1/4 teaspoon paprika, the cilantro and a pinch of salt in a bowl. Top the chicken with the yogurt sauce and serve with rice, if desired.