Slice eggplant lengthwise into 5-6 pieces (3-4 mm / ⅛ inch thick). Sprinkle with salt, let sit 10 minutes, pat dry.
Grill slices on a grill pan with ½ tosp oil for 2-3 minutes per side until striped. Cool.
Mix cream cheese, Parmesan, mozzarella, egg, oregano, garlic powder, black pepper, and red pepper flakes.
Preheat oven to 190°C (375°F). Pour 100 g marinara sauce into a 22x15 cm (8.5x6 inch) baking dish.
Place 1-1.5 tosp filling at one end of each slice, roll up. Repeat with all slices.
Arrange rolls seam-side down in the dish. Bake 20-
25 minutes.