Pre-heat the oven to 425°.
Place the potatoes in a pot, cover with cold water and cover the pot with a lid. Bring to a boil, then salt the water and cook the potatoes until tender, 12-15 minutes. Drain the potatoes and add them back to the pot.
While the potatoes are working, in a large bowl, combine the ground meats with 1/2 cup cheese, 1/2 cup breadcrumbs, a splash of cream, the egg, parsley, half of the chopped garlic, the Worcestershire sauce and allspice; season with salt and pepper.
Drizzle 1 tablespoon of EVOO onto a baking sheet, form the meat mixture into four loaves about 1-1 1/2 inches thick and place on the baking sheet. Drizzle with 1 tablespoon of EVOO. Bake the loaves for 20 minutes. Wash your hands after handling the raw meats.
While the meatloaves bake, in a large skillet, heat the remaining 2 tablespoons of EVOO, two turns of the pan, over medium heat. Add the remaining garlic, carrot, onion and bay leaf and cook until tender, 7-8 minutes; season with salt and pepper and the rosemary. Stir in the tomato paste and cook for 1 minute. Whisk in the broth and simmer until thickened. Discard the bay leaf.
Add the remaining 1/3 cup cream and 1 cup cheese to the potatoes and season with 1 teaspoon salt; smash to desired consistency. Divide the potatoes among four plates and make a small well in the center. Remove the meatloaves from the oven, turn in their sauce and set alongside the potatoes. Spoon extra sauce into the wells and over the meatloaves.