In a 4-quart saucepan, sauté onion, bell pepper, carrot, and celery in olive oil until soft. Add garlic, ginger and curry powder and sauté about a minute. Add tomatoes and bay leaf and cook uncovered until tomatoes are slightly reduced, about 3 minutes. Add broth and sweet potatoes and bring to a boil. Reduce heat to low and simmer about 8 minutes. Stir in edamame, cilantro and peanut butter until combined. Continue to simmer another couple minutes until thoroughly heated. Stir in spinach and cook until wilted. Season with salt and pepper to taste.