Brown beef, remove from pan and add olive oil. When hot, add flour and brown well (to a caramel color). Stir often, and watch closely so flour doesn’t burn. Add the stock and mix well. Bring it to a boil. Add the veggies and beef. Pour into casserole dish and cover with the mashed potatoes (and cheddar cheese) and bake for 30-45 minutes at 350 degrees. Serve with your favorite bread.