1.Quarter capsicums, discard seeds and membranes. Cook capsicum on heated oiled barbecue until skin blisters and blackens. Cover capsicum pieces in plastic or paper for 5 minutes then peel away skin; slice capsicum thickly.
2.Combine oil, 1 crushed clove of garlic, 1 teaspoon finely grated rind and half the rosemary in small bowl.
3.Brush onion, leek, eggplant, zucchini, mushrooms and 3 unpeeled garlic cloves with oil mixture; cook vegetables, in batches, on heated oiled barbecue until tender.
4.Squeeze cooked garlic into small jug; discard skins. Whisk in remaining rosemary, mayonnaise and 1 tablespoon lemon juice. Serve vegetables with dressing.