Grilled Ratatouille Muffaletta

In a colander, toss eggplant with 3/4 teaspoon salt. Let stand 30 minutes.

Meanwhile, in a food processor, pulse olives, pepperoncini, and parsley until very finely chopped. Transfer to a small bowl and stir in mayonnaise.

Heat a grill or grill pan to medium. Clean and lightly oil hot grill. Toss eggplant, tomatoes, and zucchini with oil and season with salt. Grill, turning frequently, until tender and slightly charred, about 4 minutes for tomatoes and about 7 minutes each for eggplant and zucchini.

Spread bread with olive mixture. Assemble sandwich with peppers, eggplant, zucchini, and tomatoes. Serve immediately or wrap in plastic and refrigerate for up to 4 hours.