I'm warning you that once you make this olive butter, you will make it all the time. Spread it on warm baguette slices, spread over chicken before roasting, or top grilled steaks with it.
If you're not a fan of lamb or don't have access to it, this recipe would also be delicious using beef tenderloin.
I highly recommend you also make these roasted potatoes.
Herbed Leg of Lamb with Olive Butter and Roasted Tomatoes
- 1/3 cup coarsely chopped shallots
- 1 cup pitted and chopped Niçoise or Castelvetrano olives (I prefer green, but use your favorite olives)
- 1/2 cup minced garlic cloves
- 1/3 cup thyme leaves
- 1/3 cup chopped parsley leaves
- 1/3 cup chopped fresh rosemary
- 3 tablespoons Dijon mustard (you can also use whole grain mustard)
- 1/3 cup plus 1/4 cup extra-virgin olive oil
- 1 stick plus 2 tablespoons unsalted butter, at room temperature
- One 5- pound well-trimmed boned and butterflied leg of lamb
- Kosher salt Pepper
- 2 pounds cherry tomatoes
- 2 thyme sprigs
- In a blender or food processor, combine the shallots, olives, garlic, parsley, rosemary, mustard and 1/3 cup of the olive oil; blend until smooth. Save the thyme for roasting the tomatoes. If you really want to add some thyme to the butter, be sure to save some for the tomatoes.
- Transfer to a bowl and stir in the butter. Reserve half the olive butter to serve with the cooked lamb.
- Arrange the lamb fat side down on a rack set over a rimmed baking sheet.
- Spread 1/2 the herb butter all over the lamb. Refrigerate until the butter firms up. This should take about 30 minutes. By waiting for the butter to firm up, it will make rolling the lamb much easier.
- Roll up the lamb with the butter inside and tie securely with kitchen twine at 1-inch intervals. Cover and refrigerate overnight. This allows all the flavors in the olive butter to flavor the meat. If you can't refrigerate it overnight, try to make time to refrigerate it for at least a few hours.
- Preheat the oven to 400°.
- Rub the lamb with 2 tablespoons of the oil and season with salt and pepper.
- Roast for about 1 hour and 45 minutes, until an instant-read thermometer inserted in the thickest part registers 130° for medium-rare.
- Transfer the lamb to a cutting board and let rest for 20 minutes. Leave the oven on.
- On a rimmed baking sheet, toss the tomatoes with the remaining 2 tablespoons of olive oil and the thyme sprigs and season with salt and pepper.
- Roast for 20 minutes, stirring, until softened, and they start to char and get wrinkly.
- Discard the strings and thinly slice the lamb.
- Serve with the roasted tomatoes and olive butter.