Preheat the oven to 400 degrees F.
In a 3.5-quart Dutch oven or large skillet, heat the olive oil over medium heat. Add the onion, carrot, celery, garlic and a little salt. Sauté for about 10 minutes and the vegetables are tender.
Increase the heat to medium high and add the ground bison and tomato paste. Cook until the bison has browned, about 7-10 minutes.
Add the beef broth, Worcestershire sauce and steak seasoning. Lower the heat and simmer for about 5 more minutes. Add a pinch of salt, dash of hot sauce and the peas. If needed, add a little more beef broth here, too. Cook for 1-2 minutes before transferring to a small baking dish.
Meanwhile, make the mashed potatoes. Peel the potatoes and cut into quarters (about 3-4 large Russets, 5-6 medium Yukon gold, or 6-7 red potatoes). Boil in a pot of salted filtered water. Drain the potatoes and mash with the ghee and a little boiling water, as well as salt and white pepper to taste. You could also add a little coconut milk creamer to make them creamier. And perhaps some grated Parmesan cheese.
Spread the mashed potatoes on top of the meat mixture. Bake in the oven uncovered for about 20 minutes.
Let sit for about 5 minutes before serving.