Grill the vegetables over hot coals. Peel the onion and wrap it in several layers of foil. Place it inside the grill.

Place the roasted peppers and tomatoes in a lidded pan. Let the eggplants cool slightly on a plate. Don't forget about the onions, they take longer to roast than other vegetables.

Peel all the vegetables. Using a sharp knife, first cut the eggplant, then the tomato, onion and sweet pepper.

Place everything in a convenient container. Crush or grate a few cloves of garlic. Add to the vegetables.