Oven Roasted Tomato Sauce

This recipe is adapted from Deborah Madison's book, Vegetarian Cooking for Everyone.  She uses thyme for a different flavor profile, but I wanted a more Italian flavored tomato sauce.  Deborah mentions in her recipe notes that while this is a viable treatment for high quality tomatoes, it is great to use on lesser quality tomatoes since the roasting concentrates their flavor.  Since many of my tomatoes were suffering from blossom-end rot, I felt this would be the best option for my sauce.

Oven Roasted Tomato Sauce
2 quarts sauce tomatoes
1 onion, thinly sliced
1 clove garlic, thinly sliced
1 large handful chopped basil (to taste)
1 small handful chopped oregano (to taste)
Olive oil
Salt and pepper to taste

1. Preheat the oven to 375 degrees.
2. Use a knife to make an "X" on the bottom (blossom) end of each tomato.  Blanch in small batches (I did 3-4) for about 30 seconds, until you notice your X expanding and pink flesh peeking through.  Transfer immediately to an ice bath.  When the tomatoes are cool enough to handle, slip off the peels.
3. Halve and core the tomatoes.  With smaller tomatoes, I didn't bother coring much. 
4. Arrange tomatoes cut side up on a baking sheet (I used stoneware), top with the onion and garlic, and drizzle with olive oil and salt and pepper.  Roast for about 45 minutes, checking to make sure the onion and garlic don't burn.  Feel free to go longer if the tomatoes don't look cooked enough to you.
5. Let cool briefly, then transfer to a food processor to puree.  Transfer the puree to a bowl.
6. Add the basil and oregano and season with more salt and pepper to taste.

This recipe yielded two Chinese-food pint containers of sauce, so about 4 cups.  I froze them for later use, but I did taste a spoonful.  It had a great sweetness to it.  In the future, I'd like to try adding both fresh and dried herbs, as well as much more garlic.