Prep Eggplant:Brush eggplant slices with olive oil and season with salt and pepper.
Grill:Heat a grill pan or BBQ to medium-high. Grill eggplant slices for 2–3 minutes per side until golden and tender. Set aside.
Assemble Stacks:Place a slice of grilled eggplant on a plate, spread with a spoonful of ricotta, top with spinach leaves. Repeat layers, finishing with an eggplant slice.