Curried Carrot Soup

3 tablespoons oil
1 large onion, chopped
1 tablespoon ginger, minced
several cloves of garlic, minced (optional)
2-4 teaspoons curry powder depending on taste
2 lbs carrots, chopped
3-4 cups chicken broth or vegetable broth
salt and pepper to taste
sour cream

Heat oil in saucepan and add onion.  Saute until softened about 10-15 minutes.  Add ginger, garlic, and curry powder.  Saute about 1 minute.  Add carrots and chicken broth.  Bring to boil, reduce to simmer, and cook until carrots are tender, about 20-30 minutes.  Puree soup and thin with water if necessary.  Add salt and pepper to taste and serve hot with a dollop of sour cream in each bowl.