1. Heat the oven to 350 degrees.
2. In a large sauté pan heated over medium-high heat, add oil and mushrooms and sauté, stirring frequently, until the mushrooms have given up their liquid and started to color, 5 to 7 minutes. Stir in the salt and pepper, then the onions (if the pan is a little dry, add an additional tablespoon oil). Cook, stirring frequently, until the onion is softened, 3 to 5 minutes. Stir in the red pepper flakes and fennel, then the garlic, cooking until the spices are aromatic, about 1 minute. Remove from heat and stir in the wine, scraping any flavoring from the bottom of the pan. Remove the mushroom mixture to a large bowl and set aside until cooled.
3. Meanwhile, combine the bread crumbs with the heavy cream and set aside to soak.
4. Line a 9- by 5- by 3-inch loaf baking dish with bacon slices (layer them in strips, hanging the edges over, or weave the strips to create a tight lattice top). If you have a few strips left over, save them for when you assemble the loaf.
5. To the cooled mushroom mixture, stir in the soaked bread crumbs, then the egg, cheese, marinara and parsley until well combined. Knead in the beef and pork until thoroughly combined, careful not to overmix.
6. Gently but firmly pack the meatloaf mixture into the prepared dish, making sure there are no air bubbles and being careful not to disrupt the bacon slices. There should be just enough mixture to fill the loaf pan and mound slightly at the top. If you have any leftover bacon strips, lay them lengthwise across the top of the meatloaf, then fold over any hanging bacon strip edges so the loaf is completely covered with bacon.
7. Very carefully invert the prepared loaf onto a 13- by 9-inch baking dish, slowly removing the loaf dish from the top of the meatloaf.
8. Bake the meatloaf for 1 hour and 15 minutes, then increase the temperature to 400 degrees and continue to bake until the bacon is crisp and a thermometer inserted into the center of the meatloaf reaches 165 degrees, 15 to 30 minutes. Remove and set the meatloaf aside to rest for at least 15 to 20 minutes before serving.