
Dijon mustard and fresh herb roasted lamb leg with oregano lemon chimichurri.
This roasted lamb leg has lots of bright spring flavors with its fresh herbs, lemon, and Dijon and is perfectly portioned for two.
If you would like to learn how to fillet a roast, check out my post for stuffed pork loin. The process for cutting the lamb is very similar, except you will want to cut the lamb 3/4 inch thick.


This is a small roast, so I decided to use two different cooking temperatures. The higher temperature is kind of like pan searing without the pan and losing all the good stuff on the outside. It quickly cooks the exterior, browning and crisping it. The lower temperature slows down the cooking allowing the interior to come to the desired temperature without burning the roast.

This recipe can easily be doubled or tripled for a larger portion of lamb leg. The cook time at 350 degrees will need to be adjusted as well. Depending upon how large your lamb leg is, it may take an additional hour to cook. Keep a meat thermometer handy and check the roast about every 20 minutes until reaching the desired temperature.
Mustard and Herb Crusted Lamb Leg
Ingredients
Lamb
- 2 pounds boneless lamb leg
- 2 tbsp dijon mustard
- 1 tbsp parsley chopped and divided
- 1 tbsp oregano chopped and divided
- 2 tsp thyme chopped and divided
- 2 tsp garlic minced and divided
- 1 tsp salt divided
- 1/2 tsp pepper divided
- 1/2 tsp aleppo pepper divided
Chimichurri
- 1 tbsp parsley chopped
- 1 tbsp oregano chopped
- 1 tsp thyme chopped
- 2 tsp garlic minced
- 2 tsp lemon juice
- 2 tbsp olive oil
- 1/4 tsp salt
- 1/8 tsp pepper
Instructions
Lamb
- Fillet the lamb into a 3/4-1 inch flat piece. Rub each side with half the mustard, oregano, parsley, thyme, garlic, salt, pepper, and aleppo pepper. Roll the lamb up fat side out and tie with butcher's twine. Let sit at room temperature for 30-60 minutes. Preheat the oven to 450 degrees. Place the lamb on a baking tray and cook in the oven for 30 minutes. Reduce the heat to 350 and continue cooking until it reaches the desired temperature. 20 minutes for medium-rare 135 degrees, 28-30 minutes for medium 145 degrees, etc. Remove from the oven and rest for 10-20 minutes. Remove the butcher's twine, slice into 1/2 inch pieces, and serve with chimichurri.
Chimichurri
- Chop the herbs and garlic. Mix all ingredients together and refrigerate until ready to use. It will stay fresh in the refrigerator for 3-5 days.