In a saucepan, melt the butter. Stir in the flour. Simmer on low heat, stirring often, until mixture turns golden and has a slightly nutty flavor, about 10 minutes. Set aside to cool.
In a large soup pot, melt the 1/2 cup butter. Add peppers, onions, garlic, shrimp and lobster. Saute until vegetables are soft and shrimp is just pink. Add white wine, brandy, tomatoes, tomato juice, clam juice, lobster base and heavy cream. Bring just to a simmer. Stir in the hot sauce, salt to taste and about 1/2 cup of the cold roux to the hot stock. For a thicker soup, add more roux as desired. Blend well and simmer for 30 minutes. Stir in the cilantro and serve.