Grant's Recipe

Preheat & Prep

Preheat oven to 400°F (200°C). If using leftover mashed potatoes, bring them to room temperature; if making fresh, prepare 4 cups of mashed potatoes and keep warm. Finely chop the onion, mince the garlic, slice mushrooms, and chop parsley.

In a large skillet over medium heat, add 1 tablespoon olive oil. Add diced bacon and cook until fat renders and pieces are crisp, about 4–5 minutes. Remove bacon with a slotted spoon and set aside on paper towel, leaving bacon fat in the pan.

Increase heat to medium-high and add the ground beef (or lamb) to the skillet. Break it up with a spoon and brown until no pink remains, about 6–8 minutes. Season with 1/2 teaspoon of the salt and 1/4 teaspoon black pepper while cooking.

Push meat to one side of the pan. Add 2 tablespoons butter to the empty side and when melted add the chopped onion and sliced mushrooms. Sauté until softened and lightly browned, about 5–6 minutes. Add minced garlic and cook 30–45 seconds until fragrant.

Sprinkle 2 tablespoons of flour over the meat-vegetable mixture and stir to coat for 1 minute to cook off the raw flour taste.

Slowly pour in 1 cup beef broth while stirring to deglaze the pan and incorporate the flour. Add 1 tablespoon tomato paste, 1 teaspoon Worcestershire sauce, 1 teaspoon Dijon mustard, and 1 teaspoon dried thyme. Stir and bring to a gentle simmer until sauce thickens, about 3–4 minutes.

Return the crisped bacon to the skillet and stir in 2 cups packed baby spinach until wilted, about 1–2 minutes. Taste and adjust seasoning with remaining 1/2 teaspoon salt, remaining 1/4 teaspoon black pepper, and red pepper flakes if using.

Transfer the filling into a 9-inch (or equivalent) shallow baking dish and spread evenly. If the mixture is very loose, let it cool for 5 minutes so the top holds the mashed potato layer.

Spoon the prepared mashed potatoes over the meat filling in dollops, then spread gently into an even layer to cover completely. If mashed potatoes are very stiff, stir in up to 2 tablespoons milk to loosen before spreading.

Sprinkle 1 cup shredded sharp cheddar evenly over the mashed potatoes. If you like, beat 1 egg with 1 teaspoon water and brush the edges of the potatoes for a glossy brown finish.

Place the baking dish on a sheet tray and bake at 400°F (200°C) for 20–25 minutes, until the cheese is melted and the top is golden. For a more browned top, switch the oven to broil for 1–2 minutes—watch closely to avoid burning.

Remove from oven and let rest 5 minutes. Sprinkle chopped fresh parsley over the top. Cut into portions and serve hot.

Leftovers keep in the refrigerator for up to 3 days; reheat covered in a 350°F (175°C) oven for 15–20 minutes or until warmed through.