How to Make It
Preheat the oven to 350°. In a small dry skillet, toast the coriander, cumin and fennel seeds over moderate heat until golden and fragrant, about 3 minutes. Transfer to a spice grinder and let cool. Grind the seeds to a fine powder.
Spread the shredded cucumber on several layers of paper towel and blot dry with more paper towels. Transfer the cucumber to a bowl and stir in the yogurt, lemon zest, garlic, cayenne and 1 teaspoon of the spice mixture; season the raita with salt and pepper.
Brush the chicken with 2 tablespoons of the olive oil and season with salt and pepper. Sprinkle the remaining spice mixture all over the breasts. Heat 2 large ovenproof skillets over moderately high heat and add 1 tablespoon of olive oil to each. Add 3 of the breasts to each skillet, skin side down, and cook until golden, about 4 minutes. Turn the breasts and continue cooking for another 3 minutes. Transfer the skillets to the oven and bake the chicken for about 8 minutes, or until just cooked through. Serve the chicken warm, with the raita.