Easy and healthy Black Bean Soup

So, last night I got home from school really late and very hungry. So I decided to make this quick dish. Made with canned beans, this soup is a quick and easy way to get a lot of protein into your diet. Serves 3. Here's the recipe:
1-15 oz. can reduced sodium black beans ( I used Bush's, but you can use whatever you have in your house.)
2 T olive oil
salt and pepper to taste
1 large bay leaf
1/3 tsp dried oregano
Cavender's Greek seasoning, salt-free (yes, I know I put it on everything. It's that good)
half a carrot, diced
1 rib of celery, diced
4 baby portabella mushrooms
half an onion
3 cloves garlic
1 c water
Half a tomato to garnish (optional)

Heat a pot on medium heat. When the pan is hot, add your olive oil. Then add your vegetables.Add in your salt, pepper, oregano, bay leaf, and Greek seasoning.  Stir frequently so that each nook and cranny can caramelize and so that they don't burn. When they are light caramel in color, add in your garlic. Keep stirring so that the veggies don't burn. Keep in mind that garlic should only be cooked for a couple of minutes. It burns easily. Now add your water and let the veggies boil for 3-5 minutes so that they get softer. Then add the black beans. There is also liquid in the can, so that's why I didn't add too much water. Cover and let the soup boil for 10 minutes. While it is still on the burner, mash with a potato masher or a fork, whatever you have, so that there is some texture. Add a couple pinches more of salt and pepper and stir. When the soup is at your desired level of consistency, ladle it up in your bowl and eat and enjoy! Don't forget to remove the bay leaf.  Mine took about 25-30 minutes to cook.