Slice the eggplant into 1/4-inch thick slices.

Place the eggplant slices on paper towels, season with salt, and let sit for 30 minutes to draw out moisture.

Pat the eggplant slices dry with paper towels.

Preheat the panini grill.

Lightly spritz the eggplant slices with olive oil and season with salt and pepper.

Grill the eggplant slices for about 7-8 minutes, turning once halfway through.

Set the grilled eggplant aside.

Slice the bread open and layer each sandwich with 3 slices of grilled eggplant, 1 slice of mozzarella, 1/2 tablespoon of pesto, and 2 slices of tomato.

Close the sandwich and lightly spray the outside with oil.

Place the sandwich on the panini press and cook until the cheese melts and the bread is toasted.

Cut the sandwich diagonally and serve immediately.