For a richer sauce, consider adding a tablespoon of tomato paste while cooking the bell peppers. To prevent the eggplant from absorbing too much oil, you can lightly brush it with olive oil instead of pouring it into the pan. Feel free to experiment with different cheeses, such as ricotta or feta, for the filling. These rolls can be assembled ahead of time and baked just before serving. Add a few minutes to the baking time if baking from cold.