Squash and Lentil Stew

I bought butternut squash since it is Fall, and couldn't figure out what to do with it.  This stew turned out superb though!  

3 tbsp olive oil

3 carrots, peeled and diced

2 ribs celery, trimmed and diced

1 medium onion, diced

1 lb. ground beef (optional, I used it)

1 medium butternut squash, peeled, seeded and diced (5 1/2 c.)

2 Tbsp. chili powder

1/2 tsp. ground cumin

1 14 1/2 oz can light and fat-free chicken broth

1 14 1/2 oz can diced tomatoes in juice

1 1/2 c. small brown or French green lentils, picked through

additional water as needed

3/4 tsp. salt

1/3 c. cilantro leaves, chopped

additional salt and pepper to taste

Heat oil in a large stockpot or Dutch oven over medium heat.  Add carrots, celery and onion and cook 5 minutes.  (This is where I also browned the ground beef).  Add squash and season with chili powder and ground cumin.  Cook 1 minute.

Stir in broth, tomatoes, 1/2 c. water, and lentils.  Cover and simmer on medium-low heat for 40 minutes, stirring occasionally.  Uncover and stir in salt.  Simmer, uncovered an additional 10 minutes.  (I just put it in the crock pot on high for a couple of hours until the squash was soft and the lentils were done to taste).  Stir in cilantro and serve.