Latin American Fish Soup

1 large onion, chopped
3 cloves garlic, minced
2 tablespoons coconut or olive oil
1 1/2 pounds white fish fillets, cut into 1-inch pieces
6 cups water, fish stock, or vegetable broth
1 13.5 oz can coconut milk
1 28-oz can diced tomatoes, or 3 large fresh, coarsely chopped
1 green pepper or poblano pepper, chopped
1 sweet potato, peeled, diced
4 cups chopped fresh spinach
1/2 teaspoon salt
1/2 teaspoon dried thyme leaves
1/2 teaspoon red pepper flakes
1/2 cup cilantro, chopped
Lime wedges
Chopped peanuts
Optional: hot sauce to taste

1. Heat oil in a large soup pot over medium heat and add onions. Cook until onion is tender, about 5 minutes. Add garlic, sweet potato, and green pepper. Stir in seasonings, tomatoes, and 6 cups water or broth. Bring to a boil, and reduce heat. Cover and simmer until vegetables are tender about 15 minutes.
2. Add coconut milk and spinach and cook 5 minutes. Add fish and cilantro and simmer about 3 minutes until fish is cooked through. Serve with chopped peanuts and lime wedges.