Olive-Stuffed Leg of Lamb

Preparation

1. Lamb:

   Step 1

   Preheat oven to 425°. Finely chop shallot, garlic, nuts, olives, anchovies, lemon zest, mint, parsley, and thyme in a food processor. With motor running, stream in 1/2 cup oil; process until blended. Season stuffing with salt and pepper.

   Step 2

   Unfold lamb on a cutting board and season with salt and pepper. Spread stuffing over top; roll up lamb from left to right. Position seam side down and tie closed with kitchen twine at 1 1/2" intervals crosswise, then once lengthwise. Transfer to a wire rack set inside a rimmed baking sheet; drizzle with oil.

   Step 3

   Roast until lamb is starting to brown, 30–40 minutes. Reduce temperature to 325° and continue to roast until a thermometer inserted into thickest part registers 125°, 35–45 minutes longer. Remove lamb from oven and tent with foil; let rest 15–20 minutes.

   Step 4

   Do ahead: Lamb can be stuffed and tied 1 day ahead; cover and chill. Bring to room temperature before roasting.

2. Assembly:

   Step 5

   While lamb rests, process cheese, garlic, lemon zest, and thyme in food processor until light, fluffy, and smooth. With motor running, stream in 1/2 cup oil; process until blended. Season herbed cheese with salt and pepper.

   Step 6

   Dress watercress in a large bowl with lemon juice and remaining 1 tablespoon oil; season with salt and pepper. Slice lamb and serve with watercress, herbed cheese, and flatbread.