Shepherd's pie is common on both sides of the pond. Sort of. True English Shepherd's pie is made with lamb, the ground beef variety popular in the states is actually Cottage pie.
1 lb. ground beef
1 Tbsp. apple cider vinegar
1 large onion, chopped
2 carrots, diced fine
1/4 c. flour
2 c. water
2 Tbsp. vegetable bouillon, preferably tomato based
1/8 tsp. black pepper
2 lb. potatoes, peeled and cut in quarters
2 egg yolks
1/2 stick butter
1/4 - 1/2 c. milk
Boil a large pot of salted water and add the potatoes.
Meanwhile season the ground beef with pepper and cook over medium heat until almost cooked through. Add the onion and carrots and sauté for 2 - 3 minutes before turning the heat up to high and adding the vinegar. Simmer on high heat until the vinegar is reduced slightly and the air isn't as acidic.
Add the flour and cook for another 2 - 3 minutes to cook. Add the water and bouillon and simmer on medium-low for 10 minutes.
Meanwhile, when the potatoes are tender drain them and mash. Add the stick of butter and the two egg yolks. Keep mixing to so the hot potatoes don't cook the eggs. Add just enough milk to make the mixture spreadable.
Spread the lamb mixture in the bottom of a baking dish. Top with the mashed potatoes. Either plop the mixture on top and spread smooth or use a pastry bag to pipe it on top.
Bake at 350* until the potatoes are golden and the stew is bubbling.