Preparation Combine mussels and wine in large saucepan over medium-high heat. Cover and cook until mussels begin to open, stirring occasionally, about 4 minutes. Using slotted spoon, transfer mussels to large bowl (discard any mussels that do not open). Pour liquid from saucepan into 2-cup measuring cup. Stir in saffron. Let cooking liquid stand 15 minutes. Add enough cream to cooking liquid to measure 1 1/3 cups. Transfer to large saucepan. Stir in tomatoes, garlic, bay leaf, and cayenne. Simmer over medium heat until sauce thickens slightly, about 5 minutes. Season with salt and pepper. (Can be made 4 hours ahead. Cover and chill mussels and sauce separately.) Heat oil in large nonstick skillet over high heat. Add salmon, rounded side down. Cook until bottom is golden, about 3 minutes. Turn salmon over. Reduce heat to low; cover and cook until salmon is opaque in center, about 4 minutes longer. Remove from heat. Leave covered to keep warm. Bring sauce in large saucepan to simmer over low heat. Add mussels in shells; stir until heated through, about 2 minutes. Stir in lemon juice. Place 1 salmon fillet on each of 4 plates. Divide mussels among plates. Spoon sauce over salmon and mussels.
Preparation Combine mussels and wine in large saucepan over medium-high heat. Cover and cook until mussels begin to open, stirring occasionally, about 4 minutes. Using slotted spoon, transfer mussels to large bowl (discard any mussels that do not open). Pour liquid from saucepan into 2-cup measuring cup. Stir in saffron. Let cooking liquid stand 15 minutes. Add enough cream to cooking liquid to measure 1 1/3 cups. Transfer to large saucepan. Stir in tomatoes, garlic, bay leaf, and cayenne. Simmer over medium heat until sauce thickens slightly, about 5 minutes. Season with salt and pepper. (Can be made 4 hours ahead. Cover and chill mussels and sauce separately.) Heat oil in large nonstick skillet over high heat. Add salmon, rounded side down. Cook until bottom is golden, about 3 minutes. Turn salmon over. Reduce heat to low; cover and cook until salmon is opaque in center, about 4 minutes longer. Remove from heat. Leave covered to keep warm. Bring sauce in large saucepan to simmer over low heat. Add mussels in shells; stir until heated through, about 2 minutes. Stir in lemon juice. Place 1 salmon fillet on each of 4 plates. Divide mussels among plates. Spoon sauce over salmon and mussels.