Preheat oven to 400˚F. Line two sheet pans with foil for easy cleanup. Brush foil generously with extra virgin olive oil. Arrange eggplant slices in even layers on prepared pans. Brush tops of eggplant slices lightly and quickly with olive oil. Work quickly as eggplant likes to absorb lots of oil. You just want to lightly coat the surface. Sprinkle lightly with salt and freshly ground black pepper.

Bake for 15 minutes, then rotate pans and bake another 20 minutes. Remove from oven and set aside

While eggplant is roasting, make the meat sauce and parmesan sauce. For the meat sauce, heat a medium-large pot or Dutch oven over medium heat. Add Italian sausage and cook until lightly browned. Break the sausage up with a metal spatula and stir occasionally, as it cooks.

Drain excess grease and reduce heat to low. Add Italian seasoning and garlic and cook, stirring continually for 2 more minutes to soften the garlic and let the spices bloom.

Add fire-roasted tomatoes to the pot and increase heat to high. Bring to a boil, then reduce heat to maintain a steady simmer. Cook for 20-25 minutes, until sauce begins to thicken, stirring occasionally. Add fresh basil and cook for 5 minutes longer. Remove from heat.

For the parmesan sauce, pour 1 cup heavy cream into a medium-size saucepan. Heat over medium heat until simmering. Reduce heat and continue to cook, maintaining a medium-low simmer, until reduced approximately in half. This will take about 10 minutes. Add Parmesan and mozzarella. Stir over low heat, until cheese is melted and sauce is smooth. Cover and set aside.

To assemble gratin, lightly grease a low enameled cast iron pan, gratin pan or low casserole. Arrange half of the eggplant in the pan. Spoon about ½ of the meat sauce over the eggplant and then repeat layers. 

Stir the Parmesan sauce well and pour over the top of the eggplant and sauce. You can leave some of the eggplant mixture showing, if desired.

Reduce temperature to 350˚F and bake gratin until bubbly and beginning to turn golden in spots, 25-30 minutes. Remove from oven and allow to sit for 10 minutes before serving. Serve in shallow bowls with crusty bread.