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Cooking with Cast Iron
Recipe
1 hr 30 min

Sweet Potato Shepherd's Pie

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Sweet Potato Shepherd's Pie
Author: Vallery Lomas

Recipe By Vallery Lomas

Published on November 3, 2025

A rich, earthy take on this classic comfort food made entirely in a cast-iron skillet.

Time

1 hr 30 min

Yield

Serves 4

Why This Recipe Works

This take on shepherd’s pie is a nod to the classic preparation with a base of highly seasoned lamb, but with a twist: Instead of the usual white potato topping, we swapped in earthy sweet potatoes. Microwaving the sweet potatoes was the fastest, easiest way to cook them, while stirring in a little half and half and butter ensured the topping was rich but not stodgy. Flavoring the lamb with warm spices—paprika, cardamom, and nutmeg—was a playful spin on the usual fare and paired beautifully with the natural sweetness of the potatoes. Using beef stock and just a tablespoon of Worcestershire sauce boosted the meatiness of the dish. Building and serving the shepherd’s pie in one skillet limited cleanup and made serving a breeze.

Ingredients

4 small sweet potatoes (8 ounces each), unpeeled, each lightly pricked with fork in 3 places
½ cup half-and-half
3 tablespoons unsalted butter, melted
1¼ teaspoons table salt, divided
1 teaspoon vegetable oil
1½ pounds ground lamb
1 teaspoon paprika
¾ teaspoon ground cardamom
½ teaspoon grated nutmeg
½ teaspoon pepper
1 onion, chopped fine
2 carrots, peeled, halved lengthwise, and sliced thin crosswise
2 tablespoons tomato paste
2 garlic cloves, minced
1 teaspoon minced fresh thyme
2 cups beef broth
2 tablespoons cornstarch
½ cup frozen peas
1 tablespoon Worcestershire sauce

Instructions

Cook along with these step-by-step instructions

step 1 imagestep 2 imagestep 3 imagestep 4 image
  1. Place potatoes on large plate and microwave until easily pierced with fork, 8 to 10 minutes. Set aside until cool enough to handle, then cut in half lengthwise and scoop out flesh; discard skins. Add sweet potato flesh to bowl and mash with potato masher until smooth. Stir in half-and-half, melted butter, and ½ teaspoon salt; set aside.
  2. Heat oil in 10-inch skillet over medium-high heat until shimmering. Add lamb, paprika, cardamom, nutmeg, pepper, and ½ teaspoon salt and cook until no longer pink, about 6 minutes, breaking up meat with wooden spoon. Using slotted spoon, transfer lamb to bowl. Discard all but 2 tablespoons fat left in skillet.
  3. Add onion, carrots, and remaining ¼ teaspoon salt to skillet and cook over medium heat, stirring occasionally, until onion is softened, about 5 minutes. Stir in tomato paste, garlic, and thyme and cook until fragrant, about 1 minute.
  4. Stir in broth, cornstarch, and lamb (discarding any lamb fat that has accumulated at bottom of bowl). Increase heat to high and bring to boil, stirring to dissolve cornstarch. Reduce heat to medium-low and simmer until sauce is thickened and carrots are tender, 8 to 10 minutes. Remove from heat and stir in peas and Worcestershire sauce.
  5. Adjust oven rack 6 inches from broiler element and heat broiler. Spread meat mixture into even layer over bottom of skillet. Using spoon, dollop sweet potato mixture evenly over filling, smoothing into even layer. Use tines of fork to make ridges over surface, then transfer skillet to oven and broil until beginning to brown in spots, about 6 minutes. Let cool for 10 minutes. Serve.

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Sweet Potato Shepherd's Pie

Recipe By Vallery Lomas

Published on November 3, 2025

Time

1 hr 30 min

Yield

Serves 4

Sweet Potato Shepherd's Pie

Ingredients

4 small sweet potatoes (8 ounces each), unpeeled, each lightly pricked with fork in 3 places½ cup half-and-half3 tablespoons unsalted butter, melted1¼ teaspoons table salt, divided1 teaspoon vegetable oil1½ pounds ground lamb1 teaspoon paprika¾ teaspoon ground cardamom½ teaspoon grated nutmeg½ teaspoon pepper1 onion, chopped fine2 carrots, peeled, halved lengthwise, and sliced thin crosswise2 tablespoons tomato paste2 garlic cloves, minced1 teaspoon minced fresh thyme2 cups beef broth2 tablespoons cornstarch½ cup frozen peas1 tablespoon Worcestershire sauce

Instructions

  1. Place potatoes on large plate and microwave until easily pierced with fork, 8 to 10 minutes. Set aside until cool enough to handle, then cut in half lengthwise and scoop out flesh; discard skins. Add sweet potato flesh to bowl and mash with potato masher until smooth. Stir in half-and-half, melted butter, and ½ teaspoon salt; set aside.
  2. Heat oil in 10-inch skillet over medium-high heat until shimmering. Add lamb, paprika, cardamom, nutmeg, pepper, and ½ teaspoon salt and cook until no longer pink, about 6 minutes, breaking up meat with wooden spoon. Using slotted spoon, transfer lamb to bowl. Discard all but 2 tablespoons fat left in skillet.
  3. Add onion, carrots, and remaining ¼ teaspoon salt to skillet and cook over medium heat, stirring occasionally, until onion is softened, about 5 minutes. Stir in tomato paste, garlic, and thyme and cook until fragrant, about 1 minute.
  4. Stir in broth, cornstarch, and lamb (discarding any lamb fat that has accumulated at bottom of bowl). Increase heat to high and bring to boil, stirring to dissolve cornstarch. Reduce heat to medium-low and simmer until sauce is thickened and carrots are tender, 8 to 10 minutes. Remove from heat and stir in peas and Worcestershire sauce.
  5. Adjust oven rack 6 inches from broiler element and heat broiler. Spread meat mixture into even layer over bottom of skillet. Using spoon, dollop sweet potato mixture evenly over filling, smoothing into even layer. Use tines of fork to make ridges over surface, then transfer skillet to oven and broil until beginning to brown in spots, about 6 minutes. Let cool for 10 minutes. Serve.
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