3Put the bread, 3 tablespoons of the oil, salt, and freshly ground black pepper into one of the trays and toss with your hands.
4Slice the tomatoes through their equators and pull the seeds and pulp out into a small bowl, then pour into a strainer over another bowl and let drain well. Discard the seeds, reserve the juice.
5Put the tomato halves side by side on the other tray.
6Sprinkle garlic, salt, pepper, sugar, and thyme over the tomatoes.
7Drizzle 3 tablespoons of oil over the tomatoes.
8Place in the oven, with the tray of bread, for 15 minutes.
9Remove the tray of bread; it will be browned and crisp. Reserve.
10Turn the oven down to 150°C and cook the tomatoes for a further 15 minutes, or until slightly shriveled.
11Remove from the oven and sprinkle each with a little balsamic. Reserve.
12Slice the onion thinly and add to the bowl of tomato juice.
13Season with salt and pepper and add the remaining 3 tablespoons of oil. This is the dressing.
14Put the spinach, roasted bread, and tomatoes on a serving platter, then spoon the dressing over everything.