Preheat oven to 400 degrees F. Place the lamb on a rack in a roasting pan. Use a paring knife to make small slits all over the lamb. Place the garlic slivers in the slits.
Place the bay leaves, fennel seeds and lavender in a spice mill or coffee grinder and grind to a powder.
Combine the herb powder, fresh herbs, olive oil and salt and pepper to form a paste.
Rub the paste over the entire leg of lamb and roast for 40 to 50 minutes. A meat thermometer placed in the center of the lamb should read 135 degrees F - 145 degrees F for medium rare.
Let the lamb rest for 10 minutes before carving.
Recipe by Culinary Thymes at https://www.culinarythymes.com/roast-leg-of-lamb-with-spring-herbs/