1. Place water, white wine, bay leaves and onion into large heavy skillet. Tie thyme, peppercorns and parsley in a layer of cheesecloth. Drop into wine mixture. 2. Bring mixture to a simmer over medium heat. Add the fish fillets. Cover skillet and continue to simmer 8-10 minutes or until fish is firm and flakes easily with a fork. Do not overcook. 3. Remove fish to a serving platter, using a slotted spoon. Remove cheesecloth bag, bay leaves and onion and discard. 4. Add tomato puree and red pepper flakes to liquid in skillet. Bring to a boil, stirring to mix well; boil until liquid is reduced by half. Add the saffron and 3 thin slices of lemon; boil 1 minute longer. 5. Spoon sauce over fish fillets and garnish with more thin lemon slices. Serve immediately.