Well I was schooled by a scot in a pub once about the fact that shepherds pie is with lamb and cottage pie is with beef.

So I don't actually have a recipe for shepherd's pie, as the wife and I can't stand lamb. But the following is a very simple recipe that my wife makes for Cottage Pie.

1lb. Ground Beef
Some corn, onion, garlic, and mushrooms.
Beef and/mushroom Gravy (some in the meat and some to top the finished pie)
Standard Italian seasoning (don't shoot me, lol)
Potatoes
Cheese
Can of Cream of Mushroom Soup

Brown the beef and add the onion, corn, mushrooms, seasoning, some gravy and the mushroom soup. Mix some cheese (I've used goat, cheddar, mozzarella, herb&garlic cream cheese, basically whatever), milk and butter when mashing the potatoes.
Pour the beef mixture into a dish and top with potatoes. Bake for a while until the tops of the potatoes are starting to turn golden, probably about 30mins.
Put some gravy on top of the servings if desired and enjoy.

I would like to add more veggies, but the wife won't let me...