In a large skillet, cook beef and sausage in oil, until crumbled and no longer pink.
Put meat in slow cooker reserving 1 T. of the liquid from the pan.
Add reserved oil, onions, carrots and celery to the pan. Cook and stir until softened. Add jalapeno, chili powder, cumin, oregano, salt and pepper. cook and stir for about 1 minute. Add ketchup and refried beans an stir well. Add stock and corn and bring to a boil. Pour over meats in slow cooker and stir well to combine.
To make the topping:
Mix dry ingredients together in a large bowl.
Mix butter, egg and milk together and pour into dry ingredients. Stir just to blend.
Fold in cheese and green chilies.
spread over meat mixture in the crock pot.
Cover and cook on low for 6-8 hours or high for 3-4 hours.
Topping will rise and get crusty and the meat will be bubbly and hot.