For the mashed potato layer:
- 2 lbs potatoes, peeled and chopped (I like Yukon Gold best, but use russet sometimes – about 4 medium russet potatoes = 2 lbs)
- 3-4 Tablespoons butter, or to taste
- 1/2 cup or more milk, to taste
- salt and pepper
For the meat mixture:
- 1 Tablespoon olive oil
- 1 medium onion, diced
- 2-3 carrots, peeled and diced
- 2 cloves garlic, minced
- 1 lb ground beef (lean! I usually use 85/15 since that’s what I buy at Costco, but 90/10 would be fine here, too)
- 1 teaspoon kosher salt
- 2 Tablespoons flour
- 2 teaspoons of tomato paste (before I started buying it in a tube that made this easy, I used 2 squirts of ketchup instead)
- 1 cup chicken broth (I use 1 cup water + 1 teaspoon Better than Bouillon)
- 1 teaspoon Worcestershire sauce
- pinches of dried herbs, such as basil, Italian seasoning, and thyme
- 1/2 cup frozen peas
- 1/2 cup frozen corn
- Start cooking the potatoes first: put peeled, chopped potatoes in a pot and cover with cold water. Bring to a gentle boil and cook, covered, until tender (about 20 minutes).
- Preheat the oven to 400. In a large, deep skillet (ovenproof if you’d like to use it to bake the pie), heat the olive oil over medium heat. Add the onion and carrots and saute 3-4 minutes. Add the minced garlic and cook and stir for another minute.
- Increase the heat to medium-high and add the ground beef, salt, and pepper to taste and brown beef, chopping it up with a wooden spoon and mixing it in with the vegetables once it begins to cook. When the meat is no longer pink, reduce the heat to medium again and sprinkle the flour over the meat. Stir to coat the beef and cook, stirring, for a minute.
- Add the tomato paste/ketchup, chicken broth, Worcestershire sauce, and pinches of dried herbs. Allow the mixture to come to a boil, then reduce heat to low and simmer, covered, for 10-12 minutes or until the sauce is thickened*.
- Add the frozen peas and corn and stir. (If you prefer, you can add the peas and corn before the meat mixture simmers. I like to add them later since it leaves them a little crisper and I like the contrast.)
- When the potatoes are tender (*hopefully, this happens while the meat mixture is simmering), drain the water and add butter, mashing the potatoes a bit with a potato masher or the beaters of a hand mixer. Add about 1/3 cup of milk and salt and pepper and mash/mix the potatoes. Taste and adjust seasoning, and add more milk until you get the consistency you like. I like to use more liquid than I normally might to make a softer mash since they’re going in the oven and I don’t want the final dish to be dry.
- To assemble the shepherd’s pie, you can leave the filling in your ovenproof skillet and spread the potatoes on top, OR transfer the filling to a deep 9×9 or 11×7 baking dish and then add the potatoes on top. Try to make sure the potatoes reach the edges to create a seal for the filling. If your pan is super full and you think it might bubble over, put the pan on a foil-lined baking sheet!
- Bake at 400 for about 25 minutes (sometimes I turn on the broiler for the last couple of minutes to brown the top).
You can make the shepherd’s pie ahead of time and store the assembled dish in the fridge until you’re ready to bake. You may need to add 5-7 minutes more baking time to ensure that it’s heated through.
I’ve never frozen this dish assembled, but I have made a double batch of the meat mixture and frozen that part in a large freezer bag. That way, I just need to thaw the meat mixture and put it in a baking dish, and make fresh mashed potatoes to top it and bake as usual.
This recipe is adapted from Alton Brown.