Jersey Royal Potato and Leek Pierogi with Brown Butter Sauce

**Make the Dough:** In a large bowl, combine the flour and salt. Make a well in the center and add the warm milk and egg. Gradually incorporate the flour into the wet ingredients until a shaggy dough forms. Knead the dough on a lightly floured surface for 5-7 minutes, until smooth and elastic. Add a little more milk if the dough is too dry. Wrap the dough in plastic wrap and let it rest at room temperature for at least 30 minutes.

**Prepare the Filling:** Boil the Jersey Royal potatoes in salted water until tender, about 15-20 minutes. Drain well and return to the pot. While the potatoes are cooking, heat the vegetable oil in a large frying pan over medium heat. Add the sliced leeks and cook until softened and translucent, about 8-10 minutes. Season with salt and pepper.

**Mash the Potatoes:** Mash the cooked potatoes with the 4 tablespoons of Jersey butter until smooth. Stir in the cooked leeks, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Taste and adjust seasonings as needed. Let the filling cool slightly.

**Assemble the Pierogi:** On a lightly floured surface, roll out the dough to about 1/8-inch thickness. Use a 3-inch cookie cutter or glass to cut out circles. Place a spoonful of the potato and leek filling in the center of each circle. Fold the dough over to form a half-moon shape and pinch the edges tightly to seal, crimping with a fork if desired.

**Cook the Pierogi:** Bring a large pot of salted water to a boil. Gently drop the pierogi into the boiling water, a few at a time. Cook until they float to the surface and are heated through, about 3-4 minutes after they rise.

**Make the Brown Butter Sauce:** While the pierogi are cooking, melt the 6 tablespoons of Jersey butter in a small saucepan over medium heat. Cook, swirling occasionally, until the butter turns a golden brown color and has a nutty aroma, about 5-7 minutes. Be careful not to burn the butter.

**Serve:** Remove the cooked pierogi from the boiling water with a slotted spoon and drain well. Toss the pierogi with the brown butter sauce and sprinkle with fresh dill. Serve immediately.