Smashed Chickpea and Eggplant Pressed Sandwich

Name: Smashed Chickpea and Eggplant Pressed Sandwich
Ingredients: 1 large eggplant (1 1/4 pounds), sliced into 1/2-inch thick rounds; Kosher salt and freshly ground black pepper; 1/4 cup plus 3 tablespoons extra-virgin olive oil; One 14.5-ounce can chickpeas, rinsed and drained; Zest and juice of 1/2 lemon; 1/2 small red onion, finely chopped (about 1/4 cup); 2 tablespoons roughly chopped fresh mint; 1 large ciabatta loaf, about 12 inches long; 1/2 cup prepared hummus; 1/2 English cucumber, cut into 1/4-inch pieces; 1/3 cup sliced pepperoncini, drained and blotted dry; 2 medium carrots, grated or shredded (about 3/4 cup)