INGREDIENTS 3/4 teaspoon cumin seeds, toasted 3/4 teaspoon coriander seeds, toasted 2 cups whole-milk yogurt 4 garlic cloves, chopped 1 (1 1/2-inch) piece fresh ginger, peeled and chopped 3 tablespoons vegetable oil plus additional for greasing pan 2 tablespoons fresh lime juice 1 1/2 teaspoons salt 3/4 teaspoon ground turmeric 1/2 teaspoon garam masala (Indian spice mixture) 1/2 teaspoon black pepper 1/4 teaspoon cayenne 5 pounds skinless boneless chicken breasts, cut into 1 1/2-inch cubes Accompaniments: mango and red pepper chutney and mint raita Garnish: lime wedges Special Equipment 20 (12-inch) wooden skewers PREPARATION Purée all ingredients except chicken in a blender until spices are well ground. Put chicken in a large bowl, or divide between 2 large sealable plastic bags, and add yogurt mixture, stirring or turning to coat. Marinate chicken, covered and chilled (turning occasionally if using bags), at least 4 hours. Soak skewers in water 30 minutes. While skewers ar...