2 TBSP butter
1/2 cup extra virgin olive oil
4 lbs tomatoes, peeled* and sliced in half with stems removed
3/4 tsp sea salt
1/2 tsp fresh ground black pepper
(optional) fresh sprigs of thyme, oregano or rosemary
1 medium sized yellow onion, diced
2 stalks celery, diced
5 medium sized carrots, diced
3 cloves garlic, minced
2 cups chicken (or vegetable) stock
1/3 cup fresh basil leaves, chopped
3/4 cup heavy cream
Place sliced tomatoes on a baking sheet. Cover with most of the olive oil (reserving 2 TBSP or so), and the salt and pepper. If you'd like a little more flavor, I sometimes add a fresh sprig or two of oregano or thyme atop the tomatoes. Place in a 400 degree oven for 30 minutes to roast.
Halfway through the roasting, melt the butter and remaining olive oil in a heavy-bottomed pot over medium-low heat. Add onion, celery, carrots, and garlic and cook until the vegetables begin to get soft (15 minutes or so). When the tomatoes are done, add those to the pot (removing the sprigs of herbs), along with the stock. Simmer on low until the vegetables are all tender (another 15 minutes or so).
Puree the soup. (I don't have an immersion blender, so my regular blender works just fine, doing it in batches.)