Preheat your oven to 350°.
In a large pan, heat the butter or olive oil over medium heat for a minute or two.
Add in the ground venison, diced onion, salt, pepper, garlic, onion powder, and garlic powder. Cook until the venison is browned. Do NOT drain.
Stir in the cornstarch and beef stock. Mix well.
Bring it to a boil over medium-high heat and cook for about 10 minutes.
Stir in the frozen peas and corn. (or whatever frozen vegetable mix you want)
White the venison is browning, prepare your mashed potatoes. Make sure you stir in the freshly grated Parmesan cheese.
Pour the cooked venison meat mixture into a 9 x 13 in. baking dish or a casserole dish.
Spread the prepared mashed potatoes evenly over the top of the meat mixture.
Bake this for 10 minutes. Broil it for 5-7 minutes or a smidge longer if you want a browned mashed potato.
Serve alongside a delicious salad or crusty rolls. Enjoy!