Wash and peel the parsnips and carrots, and cut into 1/2 inch rounds. Place these into a large pot with the bone broth. Cover with a lid, and allow the bone broth to come to a simmer and cook until tender, approximately 10 minutes. If broth evaporates, add more broth or water so vegetables don’t scorch the bottom of the pan.
While the vegetables are boiling, preheat a large skillet over medium high heat. Once preheated, add the lard or grease, as well as the meat, spices, and mushrooms. Sautee until the meat is cooked through and the mushrooms are tender. Turn off heat.
Once carrots and parsnips are cooked through, pour any remaining broth and the cooked vegetables into a high speed blender or a food processor. Season with salt to taste. Blend until smooth. Add more broth if necessary to thin.
Scoop carrot-parsnip mash out of the food processor and dollop onto the meat and mushroom mixture, smoothing it out with a large spoon as you go, to cover the meat.
Place into oven on broil, if you want to get the outer crust crispy. Or serve as is with no additional cooking.