1 large eggplant, (1 and 1/4-1 and 1/2 pounds), cut into 12 1/4-inch-thick rounds
4 small pieces focaccia or rustic Italian bread
Canola or olive oil cooking spray
2 teaspoons extra-virgin olive oil
1/4 teaspoon salt
5 ounces baby spinach
3 tablespoons finely shredded Parmesan or Asiago cheese
1 cup crushed tomatoes, preferably fire-roasted
1/2 cup shredded part-skim mozzarella cheese
3 tablespoons chopped fresh basil, divided
Preheat grill to medium-high.
Place eggplant rounds on a baking sheet and sprinkle with salt. Coat both sides lightly with cooking spray.
Combine Parmesan (or Asiago) and mozzarella in a small bowl. Brush both sides of focaccia (or bread) with oil.
Place spinach in a large microwave-safe bowl. Cover with aluminium wrap and punch several holes in the wrap. Microwave on "High" until wilted, 2 to 3 minutes.
Combine tomatoes and 2 tablespoons basil in a small microwave-safe bowl. Cover and microwave until bubbling, about 2 minutes.
Place all your ingredients on the baking sheet with the eggplant and take it to the grill. Grill the eggplant slices until brown and soft on both sides, 2 to 3 minutes per side.
Grill the bread until toasted, about 1 minute per side. Return the eggplant and bread to the baking sheet. Reduce grill heat to medium.
Place 1 eggplant round on top of each slice of bread. Layer 1 tablespoon tomatoes, 1 tablespoon wilted spinach and 1 tablespoon cheese on each slice of eggplant. Repeat with the remaining eggplant, sauce, spinach and cheese.
Sprinkle each stack with some of the remaining basil. Place the baking sheet on the grill, close the lid and grill until the eggplant stack is hot and the cheese is melted, 5 to 7 minutes.