Shepherds Pie with Northern Isles Lamb Sausage and Potato-Horseradish Crust

• 2 pounds russet or Yukon gold potatoes, or a mixture
• Kosher salt
• 1/2 cup milk
• 4 tablespoons butter, at room temperature
• 1 1/2 teaspoons freshly grated horseradish or unseasoned prepared horseradish
• 1/2 teaspoon freshly ground white pepper
• 2 tablespoons butter
• 16 pearl onions, peeled
• 2 carrots, peeled and finely chopped
• 2 ribs celery, finely chopped
• 1 pound Northern Isles Lamb Sausage (page 105)
• 1 teaspoon chopped fresh thyme or 1/2 teaspoon dried thyme
• 2 tablespoons tomato paste
• 2 dashes of Worcestershire sauce
• 1 teaspoon kosher salt
• 1/2 teaspoon freshly ground white pepper
• 1 cup water

1. To make the crust, peel the potatoes and cut them into 1 1/2-inch chunks.
2. Place them in a pot, add water to cover generously and a large pinch of salt, cover, and bring to a boil over high heat.
3. Boil briskly until the potatoes are a bit beyond fork-tender, almost collapsing, about 10 minutes.
4. Drain in a colander and, while the potatoes are still moist, return them to the pot.
5. Let cool briefly until no longer steaming.
6. Add the milk, butter, and horseradish and mash with a potato masher or sturdy wire whisk until no longer chunky, almost creamy.
7. Whisk in 1 teaspoon salt and the pepper, taste, and adjust the seasoning with more salt and pepper if desired.
8. Set aside in a warm place.
9. Preheat the oven to 400F.
10. To make the filling, melt the butter in a large saute pan over medium heat.
11. Add the pearl onions, carrots, and celery, stir to mix, and cook, stirring occasionally, until the vegetables are slightly softened, about 5 minutes.
12. Add the lamb sausage and continue cooking, stirring to break up the clumps, until no longer pink, 3 to 4 minutes.
13. Add the thyme, tomato paste, Worcestershire, salt, pepper, and water and stir to mix.
14. Bring to a boil over medium heat and cook until slightly thickened, about 3 minutes.
15. To assemble the pie, transfer the filling to a 2-quart baking dish, preferably one that can segue from oven to table for ease of serving.
16. Spread the mashed potatoes across the top and, with a fork or spoon, lift them into decorative peaks here and there.
17. Bake until the top is golden around the edges and across the peaks, 30 to 35 minutes.
18. Serve hot, directly from the baking dish.

russet, kosher salt, milk, butter, freshly grated horseradish, freshly ground white pepper, butter, pearl onions, carrots, celery, sausage, thyme, tomato paste, worcestershire sauce, kosher salt, freshly ground white pepper, water

Taken from www.epicurious.com/recipes/food/views/shepherd-s-pie-with-northern-isles-lamb-sausage-and-potato-horseradish-crust-389525 (may not work)