Tomato Basil Parmesan Soup

1 cup finely diced celery
1 cup finely diced carrots
1 cup finely diced onions

2 (14 oz) cans diced tomatoes, with juice
1 tsp dried oregano or 1 T fresh oregano
1 T dried basil or 1/4 cup fresh basil
4 cups chicken broth
1 bay leaf

½ cup flour
½ cup butter

1 cup Parmesan cheese
1.5 cups half and half, warmed 
1/2 tsp salt
¼ tsp black pepper

DIRECTIONS

Put in food processor and blend until almost smooth: celery, carrots, and onions. 
In a large dutch oven saute the pureed vegetables 5 mintues. 
Add tomatoes, oregano, basil, and bay leaf  and broth.
Cook on low for 2-3 hours.

About 30 minutes before serving prepare a roux. Melt butter over low heat in a skillet and add flour. Stir constantly with a whisk for 5-7 minutes. Slowly stir into hot soup.  
Stir and add the Parmesan cheese, warmed half and half, salt and pepper. Add additional basil and oregano if needed.
Cook on LOW for 20 minutes or so. Too high of a temp,  and the milk will curdle-DON'T DO IT!