You can also do this on the grill.
Slice 1 lb. of Roma tomatoes lengthwise.
Mince 4 cloves of garlic.
Remove leaves from 1 bunch of basil to make 1 C., then chop roughly.
Pour 2 T. olive oil onto a cookie sheet or large pyrex baking dish. Arrange the garlic and basil more or less evenly around the pan, then sprinkle with salt and pepper. Add a pinch of other fresh or dried herbs if you like.
Place the tomatoes face down on the pan. Roast for 30-40 minutes. Remove from the oven and allow to cool
Remove the tomato skins, then pour the sauce into a bowl. Use a spatula to get all the good bits. Mash a bit with a fork, or if necessary puree for a minute in the food processor.