Vegetarian Lentil Soup

I just made this again the other night and changed a few things. It had a lot more flavor and I really liked it. So, here are the adjustments.

1 onion, chopped (I didn't have a fresh onion, so I did 3 T. dried, minced onion)
1/4 c. olive oil
2 carrots, diced
2 stalks celery, chopped
3 cloves garlic, minced
1 1/4 tsp. dried oregano
1 bay leaf
1 1/2 tsp. dried basil
1 (14.5 oz.) can diced tomatoes
2 c. dried lentils
8 c. water
3/4 c. frozen, chopped kale (or you can use spinach fresh or frozen)
2 T. balsamic vinegar
1 tsp. salt (or more to taste)
1/2 tsp. black pepper (optional, to taste)

Directions
Makes 6 servings

In a large soup pot, heat oil over medium heat. Add onions, carrots, and celery; cook until onion is tender. Stir in garlic, bay leaf, oregano, and basil; cook for 2 minutes. Stir in lentils, and add water and tomatoes. Bring to a boil, reduce heat and simmer for 1 hour. Add frozen spinach and cook until tender. Stir in vinegar, salt, and pepper.

(I had to leave home while this was cooking, so I ended up putting it in the crockpot. I turned it on high and left it for about 2-3 hours and then added the kale and balsamic vinegar and let it cook on low until we were ready to serve it.)