Muffuletta Picnic Sandwich

Ingredients

• • 2 red bell peppers, each cut into 3 pieces and seeded
  • 3 zucchini, cut lengthwise into 1/4-inch (5 mm) thick slices
  • 1 large eggplant, about 3/4 lb (340 g), cut into 1/4-inch (5 mm) thick slices
  • 3 tbsp (45 ml) olive oil
  • 1 tbsp (15 ml) balsamic vinegar
  • 1 loaf round Italian bread, about 8 inches (20 cm) in diameter
  • 1/4 cup (60 ml) ajvar spread (see note)
  • 3 oz (85 g) mortadella slices
  • 2 oz (55 g) calabrese sausage slices
  • 1/2 cup (20 g) fresh basil leaves