Bring water to a boil in a 2-quart saucepan, then add rice, onion, garlic, bay leaf, salt, and pepper to taste. Return to a boil, cover, and reduce heat to low. Cook until rice is tender and liquid is absorbed, 15 to 17 minutes. Fluff rice with a fork and let stand, covered, 5 minutes. Stir in herbs just before serving.
Pat fillets dry and sprinkle with cumin and salt and pepper to taste on both sides.
Heat oil in a well-seasoned 10-inch cast-iron skillet over high heat until hot but not smoking, then sear fillets until browned on 1 side, about 5 minutes. Turn fillets over and put skillet in oven. Roast fillets in upper third of oven until just cooked through, 6 to 8 minutes.
Whisk together broth, juice, molasses, and cornstarch in a small skillet and simmer, whisking, until slightly thickened, 4 to 5 minutes. Halve each fillet crosswise and serve over rice. Spoon sauce over and around fish.
Each serving, including rice, about 301 calories and 4 grams fat.
