Step by step

1. Prepare the lamb: Using a vegetable peeler, peel the lemons, leaving the white pith behind. Reserve the lemons. Strip the leaves from two sprigs of rosemary. In the bowl of the food processor (fitted with the S-blade), combine lemon peel, rosemary leaves, fennel seed, 1 Tbsp. lavender flower, garlic, black peppercorns, 1 tsp. salt and 3 Tbsp. of olive oil. Pulse until the mixture is finely ground, scraping down the sides of the bowl as needed. Set aside.

2. Pat the lamb leg dry with a paper towel. Rub the underside of the lamb leg with 1 Tbsp. of olive oil. Working with a few tablespoons at a time, cover the top surface and sides of the lamb with the lemon-rosemary herb mixture by pressing firmly on to the lamb. Thinly slice one of the lemons. Set aside.

3. Make the salt crust: Preheat the oven to 177°C. In the bowl of the stand mixer fitted with the wire whip, whip the egg whites on speed 4 until frothy, about one minute. Add the remaining 2 Tbsp. of lavender and whip for another minute. Reduce to speed 1 and add the salt in three additions, alternating with the water. Scrape sides of bowl as needed. Add enough water until the salt mixture looks and feels like wet sand when squeezed in your hand.

4. Transfer a quarter of the lavender-salt mixture (about two cups) to the baking sheet and roughly form into the shape and size of the lamb leg, about ¼-inch thick. Place the reserved lemon slices over the salt bed and scatter the remaining two rosemary springs and bay leaves on top. Place the lamb leg on top of the salt bed. Starting at the bottom and working your way to the top, cover the lamb with small handfuls of the lavender salt, carefully covering the meat. Gently press the salt together to form a sealed crust.

5. Roast the lamb for 1 hour or until an instant-read thermometer inserted in the thickest part without touching the bone registers 54°C for medium-rare temperature. Set aside and allow the meat to rest for 20 minutes.

6. Serve the lamb: Using a serrated knife, cut around the base of the salt crust. Lift the crust off the lamb and discard. Lift the lamb leg from the salt base and place on a cutting board. Slice the lamb against the grain and place on a serving platter. Garnish with rosemary and lavender, if desired.