Thaw fish, if frozen. Rinse fish; pat dry with paper towels.
Fill a 12-inch skillet with water to a depth of 1 inch. Bring water to boiling; reduce heat. Arrange sweet pepper, green beans, and carrot in a steamer basket. Place fish on top of vegetables. Sprinkle fish and vegetables with salt and black pepper. Place steamer basket over simmering water. Cover and simmer gently for 6 to 8 minutes or until fish begins to flake when tested with a fork.
Meanwhile, for sauce, in a small saucepan combine coconut milk, lime juice, fish sauce, ginger, and crushed red pepper. Bring to boiling; reduce heat. Boil gently, uncovered, for 2 to 3 minutes or until slightly thickened.
Remove fish and vegetables to serving plates. Drizzle with sauce and sprinkle with peanuts and cilantro.