4 hours. Yields about 16 (1-cup) portions
3 large red bell peppers, quartered, stem, seeds and ribs removed
3 large yellow bell peppers, quartered, stem, seeds and ribs removed
2 cups olive oil, preferably French or other buttery and rich flavored oil
4 1/2 pounds plum or paste tomatoes (15 to 18 tomatoes)
9 sprigs thyme
9 sprigs parsley
3 fresh bay leaves
3 cups finely diced onions
Salt and freshly ground pepper to taste
3 tablespoons finely minced garlic
1 pound yellow zucchini (2 to 3 zucchini), cut into ½-inch dice
1 pound green zucchini (2 to 3 zucchini), cut into ½-inch dice
1 1/2 pounds eggplant (approximately 1 eggplant), cut into ½-inch dice
Balsamic vinegar, to taste
1. Heat the oven to 450 degrees. Coat the peppers with a thin film of olive oil (about 2 tablespoons), then place the peppers, flesh side down, on a foil-lined baking sheet. Roast until the skin begins to loosen, then remove from the oven, 10 to 15 minutes. Transfer the peppers to a plastic bag, and set aside to steam until they are cool enough to handle. Peel the peppers. (As an alternative to roasting the peppers, you can use a blowtorch to char the skins of the peppers while they are still whole, and then gently scrub the charred skin off under running water to remove the skins.) Dice the peeled peppers into one-half-inch pieces and set aside. Reduce the oven temperature to 350 degrees.
2. Bring a small pot of water to a rapid boil. Stem the tomatoes and score the skin on the bottom into an X. Plunge one tomato at a time in the boiling water until the skin begins to loosen, about 15 seconds. Immediately transfer the tomato to a bowl of ice water to stop the cooking. Repeat this process with the remaining tomatoes. Remove the tomatoes from the ice water and peel the tomatoes. Dice the tomatoes into one-half-inch pieces, saving all the juice, then set them aside.
3. Cut the thyme sprigs, parsley sprigs and bay leaves into approximately 1-inch lengths. Place the herbs in the center of an 8-inch-square piece of cheesecloth. Gather the ends of the cheesecloth around the herbs, and twist them to form the herbs into a sachet. Tie the sachet securely with a piece of butcher's twine.
4. Heat a wide, shallow pot or roasting pan over medium heat and add one-half cup oil. Add the onions and the sachet of herbs to the pot along with a good pinch of salt — this will help release the liquid inside the onions and allow them to sweat without coloring. Sweat the onions until they are soft and translucent, about 10 minutes. Add the garlic and sweat until it is fragrant and the raw flavor has subsided, about 2 minutes.