Drain and coarsely chop tomatoes, reserving liquid. Cook green peppers and onion in butter in large saucepan until tender but not brown. Stir in flour. Add tomatoes, reserved liquid, chicken, 1 teaspoon of the salt, thyme or gumbo file and hot pepper sauce. Cover and simmer for 20 minutes.
Meanwhile, bring 2 cups of water to a boil in large saucepan. Stir in rice, butter and remaining 1 teaspoon salt. Cover tightly and simmer for 20 minutes. Remove from heat. Let stand covered until all liquid is absorbed, about 5 minutes. Add shrimp to gumbo and continue cooking for another 5 minutes. Stir parsley into rice. To serve, spoon stew into individual serving bowls; top with rice.
