Preparation Heat oil in heavy large Dutch oven over medium heat. Add shrimp shells; sauté 3 minutes. Add carrots, leeks and onion and sauté 5 minutes. Add wine; simmer 5 minutes. Add water, 3/4 bunch cilantro, vanilla and bay leaves. Cover; simmer over low heat 30 minutes. Strain stock into large saucepan. (Can be made 1 day ahead. Chill.) Bring stock to boil. Add green beans, asparagus, snow peas and 3/4 cup green onions and simmer 1 minute. Add shrimp and scallops; simmer until shellfish are cooked through, about 3 minutes. Mix in 1/2 cup green onions. Ladle soup into bowls. Sprinkle with chopped cilantro.
Preparation Heat oil in heavy large Dutch oven over medium heat. Add shrimp shells; sauté 3 minutes. Add carrots, leeks and onion and sauté 5 minutes. Add wine; simmer 5 minutes. Add water, 3/4 bunch cilantro, vanilla and bay leaves. Cover; simmer over low heat 30 minutes. Strain stock into large saucepan. (Can be made 1 day ahead. Chill.) Bring stock to boil. Add green beans, asparagus, snow peas and 3/4 cup green onions and simmer 1 minute. Add shrimp and scallops; simmer until shellfish are cooked through, about 3 minutes. Mix in 1/2 cup green onions. Ladle soup into bowls. Sprinkle with chopped cilantro.