Hearty tomato bean stew

This is a great winter stew - very filling and delicious.  I used polish sausage to impart a smokey flavor, but this would also be great without it in its vegetarian version.  Adapted from Smitten Kitchen.

Ingredients

olive oil
1 large piece of polish sausage, chopped into small chunks
1 onion, diced
2 stalks celery, diced
2 carrots, diced
3 cloves garlic
pinch of crushed pepper flakes
2 cans cannellini beans, drained
2 bay leaves
2 14oz cans chpped tomatoes
2 T tomato paste
boiling water
parsley and parmesian for garnish

Instructions

1) Heat 2 T olive oil in a large pot over medium heat.  When hot, add sausage and cook until it starts to lightly brown.
2) Add onion, celery, garlic, and carrots, along with a pinch of salt.  Cook for 5 minutes, until vegetables start to soften.
3) Add tomato, beans, bay leaves, and just enough boiling water to cover the ingredients in the soup.  Bring to a simmer and cook for 40 minutes, until the beans and vegetables are tender.
Garnish with sprigs of parsley and grated parmesian.