Gluten-Free lentil soup recipe

My friend recommended this as tasty, healthy, possibly vegetarian, high in protein and gluten free.  I plan to try it ASAP! Let me know if any of you guys try this.

Combine ingredients into a slow cooker on high for 4 hours or low for 8 hours:

* 2 stalks celery, chopped
* 3 carrots, chopped
* 1 onion, diced
* 4 cloves garlic, minced
* 3 bay leaves
* 8 cups water or GF vegetable broth or GF chicken broth
* 1 3/4 cups green lentils
* 2 potatoes, chopped
* 1 bunch spinach, chopped

I didn't but you can add these after the soup finishes cooking (I thought it was tasty enough without them):

* 1 tsp salt
* 3 tbsp red wine vinegar