Fish and Sweet Potato Chowder

Name: Fish and Sweet Potato Chowder
Ingredients: 1 tbsp. olive oil; 1 medium-size onion (chopped coarsely); 3 cloves garlic (chopped finely); 1 pimento pepper (chopped finely); 1 medium-size red sweet potato (cut into 2 cm pieces); 1 carrot (chopped coarsely); 6 cups water or fish stock; 200 g firm white fish fillet (cut into bite-size pieces (about 1inch)); 1 tsp. oregano; 2 tsp. celery (chopped); 1 tsp. parsley; 1/2 tsp. grated nutmeg; green seasoning to season fish; 1/2 cup cooking cream; Chopped chadon beni (to garnish); Sal and pepper to taste