Brown beef, then stir in onion and garlic, cook until fragrant, add in frozen veggies
Season, then pour in flour solution to thickened, take off of heat
Spread beef on rectangular pan
Grate cheese and sprinkle some on top of the beef
Make mash potato of the steamed potatoes, with butter, milk, and season it with chicken bouillon powder, fold in some of the grated cheese. Spread mashed potatoes on top of the beef.
Sprinkle top with more cheese and bake for 20 mins on preheated 400 F, then sprinkle with the rest of the grated cheese, bake for another 10 mins
Slice and serve