Spinach Tomato Soup

3 T butter
1/2 onion, chopped
3 cloves garlic, minced
2 jars spaghetti sauce
1 can diced tomatoes (Italian)
1 box chicken broth (32 oz)
2 handfuls spinach, chopped
seasonings

Saute onion and garlic in butter over medium heat in a stock pot.  Once translucent, add spaghetti sauce and diced tomatoes and turn up heat.  Once it starts to boil, add chicken broth.  Chop up spinach and add to soup.  Mix in seasonings.  I used salt, pepper, oregano, and basil.  Turn down heat and let simmer until spinach has wilted. 

Optional:  Mix in cheese or serve with grilled cheese.