Grilled Chicken and Vegetable Mozzarella Melts

Ingredients

• 5 tablespoons olive oil, divided, or more if grilling the entire vegetables
• 1 1/2 tablespoons white wine vinegar
• 1 teaspoon dried oregano
• 3/4 teaspoon kosher salt, divided, or more as needed
• 1/2 teaspoon freshly ground black pepper, divided, or more as needed
• 2 cloves garlic, coarsely chopped
• 4 skinless boneless chicken breasts (about 6 ounces each), pounded to 1/2-inch thick
• 1 small globe eggplant (about 1 pound), trimmed
• 1 medium red bell pepper, stemmed and seeded
• 1 medium sweet onion, such as Vidalia
• 1/4 cup prepared marinara sauce, at room temperature
• 2 ounces fresh mozzarella, very thinly sliced
• 4 fresh basil leaves, or more to taste

Method

1. In a small bowl, whisk together 3 tablespoons of the oil, the vinegar, oregano, 1/2 teaspoon of the salt and 1/4 teaspoon of the pepper. Transfer to a zip-top bag, add the garlic, then the chicken. Seal, pressing out the air, and squish to distribute the marinade. Refrigerate for at least 30 minutes and up to 8 hours.
2. Slice the eggplant, pepper and onion in half horizontally. Cut each into eight 1/4-inch thick slices or rounds. (You'll use about half of each vegetable. Cook all the slices and reserve the rest, or reserve them uncooked. If using the entire vegetables, brush with additional oil and season with additional salt and pepper.)
3. Preheat a grill or grill pan over medium-high heat. Brush the vegetables on both sides with the remaining 2 tablespoons of oil and sprinkle with the remaining 1/4 teaspoon each of salt and pepper. Grill, in batches if necessary, until tender with grill marks, 3 to 4 minutes per side.
4. Remove the chicken from the marinade, shaking off any garlic. (Discard the marinade.) Reduce the grill heat to medium and grill the chicken until nearly cooked through, 3 to 4 minutes per side. Transfer to a cutting board or large plate.
5. Spoon 1 tablespoon of the marinara over each piece of chicken. Top with two slices each of the grilled eggplant and pepper, then a few grilled onion slices. Distribute the cheese on top, return the stacks to the grill, cover and grill until the chicken is cooked through and the cheese is melted, 3 to 5 minutes. Top each with basil and serve.