Sweet Potato Lentil Soup

This soup is very easy to make and it tastes amazing.  I also like it because the lentils are a great source of protein and iron.  I found this recipe in Vegetarian Comfort Food: Meals That Mom Makes, Without the Meat by Jennifer Warren.  I took out the 2 teaspoons of salt because my vegetable stock contains enough salt.  I use safflower oil, but the original recipe calls for olive oil.  When I don't have leeks on hand I just add another onion. 

1 1/2 cups dried red lentils, rinsed
3 medium onions, chopped
3 carrots, peeled and chopped 
2 leeks, greens removed and whites chopped
2 tablespoons safflower oil
1 tablespoon butter
2 medium sweet potatoes, peeled and chopped
1-2 teaspoons powdered sage
2 bay leaves
6 cups vegetable stock


Put the rinsed lentils in a large bowl, covering with at least 4 inches of cold water.  Let stand for 1 hour.  While the lentils are soaking, peel and chop the vegetables.  


In a large pot, saute the onions, carrots, and leeks in oil and butter on medium heat for 8-10 minutes.  Add the sweet potatoes and saute for 3-4 minutes.  Drain the lentils and add to the pot with the sage and bay leaves, stirring thoroughly.  


Add the stock.  Simmer partially covered, stirring occasionally, for 45-60 minutes, or until the sweet potatoes and carrots are soft.  Using a blender or food processor, puree the soup until smooth, and return to the pot.