Tomato Basil Buttermilk Soup

I ran across this recipe in a grocery store magazine. I made it last night and it was delicious! Perfect for a snowy day. Enjoy!

2 T  extra-virgin olive oil
1/2  medium onion, chopped
3  cloves garlic, chopped
1  large carrot, diced
1  (28 oz) can whole tomatoes, with juices
1 3/4  cups low-sodium vegetable broth
1/4 t  salt
1/4 t  sugar
1/8 t ground black pepper
pinch of crushed red pepper flakes (optional)
2 T  finely chopped fresh basil or 2 t dried
3/4 C  fat free buttermilk

1. Heat oil in a large saucepan over medium heat. Add onion, garlic, and carrot, lower heat to medium low, and cook, stirring occasionally, until the onions are translucent and the carrots are lightly softened, about 10 minutes.

2. Add tomatoes and their juices, broth, salt, sugar, black pepper, and crushed red pepper. With a large fork or potato masher, mash tomatoes slightly to break them up a bit. Bring mixture to a boil over medium-high heat, then lower to a simmer and cook, covered, until carrots are tender, about 20 minutes.

3. Remove soup from heat and puree it using an immersion blender or a blender. (You can leave it a bit chunky if you prefer.) Stir in the basil and buttermilk, and serve at once, or let cool and refrigerate until ready to serve. To reheat, place over medium-low heat, stirring occasionally, until just heated through; do not boil. The soup may also be served cold.