Cut the potatoes into cubes and boil until tender to a fork.
In a separate skillet while the potatoes are cooking chop the carrots (if using) and onions into bite sized pieces and cook with the ground beef until beef is almost browned.
Quarter the mushrooms and add into the beef mixure if using.
Add in gravy packet and 1 C milk. Still over heat until thickened.
Add red wine and cook the alcohol off (this is optional but I like the extra depth of flavor it adds) If you don't do alcohol or don't have any on hand feel free to omit or substitute with beef broth.
Add salt and pepper to taste.
Once the potatoes are cooked drain and set aside.
In the pot the potatoes were cooked in melt butter, add garlic and milk to heat.
Add potatoes back in and mash and stir.
Add salt and pepper to taste.
Pour your beef mixture into an greased oven proof dish (I like to use a 8×8 glass casserole dish or a bread pan).
Next pour your corn on top of the beef layer.
Spoon your potatoes on top of the corn.
Finally sprinkle generously with Parmesan cheese.
Broil until the cheese layer is golden brown. Serve with pride.