Cut tomatoes in half (I prefer to leave the skin on but you can peel first). Place tomatoes and garlic (skin left on) on a baking tray and drizzle with olive oil. Season and roast in a pre-heated oven at 180 degrees for one hour.
Add vegetable stock and simmer for five minutes on a low heat. Set aside. Squeeze the flesh from the garlic cloves discarding the skin and add to stock along with the tomatoes and all of the juices from the baking tray.
Blend in food processor or hand blender and bring back to simmer. Serve with grated pecorino and toasted ciabatta.