A HERO OF A SANDWICH, this sublime combination of intensely flavored olives and roasted vegetables is almost without equal in the world of sandwiches. The New Orleans original is loaded with meat, but the signature flavor comes from the olive relish that permeates each bite. This may be a humble sandwich, but packed along on a picnic (don’t forget the napkins), it is the ultimate in food-to-go. Note that the olive relish must be made in advance to allow time for the flavors to blend.

SERVES 6

INGREDIENTS

OLIVE RELISH:

• 1 roasted red pepper, finely chopped
• ½ cup finely chopped brine-cured green olives, such as Picholine
• ½ cup finely chopped brine-cured black olives, such as Kalamata
• ½ cup finely chopped celery
• ¼ cup finely chopped fresh parsley leaves
• 2 teaspoons finely chopped fresh oregano leaves
• 1 garlic clove, minced
• ¼ cup extra virgin olive oil
• ¼ cup freshly squeezed lemon juice

VEGETABLES:

• 1 large eggplant (1¾ to 2 pounds), peeled and sliced lengthwise into ⅜-inch-thick steaks
• 5 tablespoons extra virgin olive oil
• 1 medium-size onion, halved and slivered
• 1 medium-size red or green bell pepper, cut into matchsticks
• ¼ pound mushrooms, trimmed and chopped

ASSEMBLY:

• 1 large (8-to 10-inch) round loaf Italian or French bread
• ⅓ pound provolone cheese, sliced

INSTRUCTIONS

1. To make the relish, combine all the ingredients in a medium-size bowl. Mix well. Cover and refrigerate for at least 8 hours or up to 4 days.
2. Preheat the oven to 400°F. Lightly oil two rimmed baking sheets.
3. To prepare the vegetables, arrange the eggplant slices in a single layer on one baking sheet and brush them on both sides with 3 tablespoons of the oil. Arrange the onion, bell pepper, and mushrooms in a single layer on the second baking sheet and drizzle with the remaining 2 tablespoons oil.
4. Place the baking sheets side by side in the oven. Roast for 10 minutes; turn the eggplant over and stir the onion mixture. Roast for about another 10 minutes, until the vegetables are browned and tender. (If the baking sheets do not fit side by side, place one on the middle rack and the other on the bottom rack and rotate them once or twice during the roasting process.)
5. To assemble the sandwich, cut the bread in half horizontally and remove most of the soft white center. Generously slather the inside of the bottom of the loaf with half the relish. Arrange half the provolone on the bread. Cover the provolone with one-third of the eggplant and then half of the onion, pepper, and mushrooms. Add another layer of eggplant, the remaining vegetables, and then the remaining eggplant. Top with the remaining provolone. Slather the inside of the top of the loaf with the remaining relish and place firmly on the bottom.
6. If you are planning to serve the loaf cold, wrap in plastic wrap and let sit for 30 minutes, or up to 4 hours. To serve warm, preheat the oven to 300°F, wrap the loaf in aluminum foil, and bake for about 15 minutes, until the cheese is melted.