8 skinless, boneless chicken breasts (about 3 lbs.)
2 cups of plain whole-milk yogurt
1 cup coarsely chopped fresh cilantro leaves and stems
1/2 large onion, coarsely chopped
1/3 cup of olive oil plus more for brushing
6 garlic cloves, coarsely chopped
1 tbsp. fresh lime juice
1 tbsp. garam masala
2 tsp. sea salt plus more for sesasoning
1 tsp frshly ground black pepper
1 2" piece fresh ginger, peeled and chopped