Roasted tomatoes and garlic

We have followed Tom Collichio's recipe for roasted tomatoes.  We bought beautiful heirloom roma tomatoes.  Tom says to slice them in half, add some full cloves of garlic toss them in olive oil with salt and pepper and sprigs of thyme.   He places them cut side down on a cookie sheet and roasts them for 20 minutes at 350, then removes the skins, lowers the temperature to 285 and roasts them for 3 or 4 more hours.  Then, discard the thyme, and freeze the garlic and tomatoes separately for later use.