THE LIVERS: Toast and grind the coriander, fennel, and cumin seeds (a mortar and
pestle will also work). In a large bowl combine all the spices with the garlic, mustard, thyme, and olive oil. Drain and pat dry the chicken livers and toss in the mixture to coat. Set aside.
THE VINAIGRETTE: In a large sauté pan, slowly cook the sliced onions in 1 tablespoon olive oil over medium-low heat until they caramelize. If they start to burn, add a little water as necessary. When the onions are a dark, golden caramel color (about 30 to 35 minutes), whisk in the vinegar, mustard, and remaining olive oil. Transfer to a bowl and set aside.
THE GRITS: Heat the milk in a medium saucepan and stir in the grits. Cook, whisking often, until the grits are tender, then add the cheese and butter and stir until melted. Season to taste with salt.
TO SERVE: Heat the grill. Remove the livers from the marinade, and salt them. Grill until they are pink in the center, and set aside. In a large bowl toss the salad ingredients with the vinaigrette (re-whisk it first). Place a mound of grits on each of four plates and top with chicken livers. Place a handful of salad over the livers and grits, and serve immediately.