This is a marinade I originally developed for prime rib and have since used successfully for lamb, as pictured, and may even try on pork.
1 whole garlic, divided into cloves and peeled
olive oil (enough to form a paste with other ingredients
20 minced sage leaves
4 minced sprigs of rosemary
coarsely ground black pepper
Start by placing some extra virgin olive oil and the garlic cloves into a blender and chopping the garlic, then add the herbs and blend until you have a nice paste consistency.
Add a bit more oil if the paste needs thinning and blend again. Add cracked black pepper and blend one last time.
Place plastic food wrap over a plate and cover the center with a thin coat of the marinade, then place your roast on top of it. Add more of the paste to the top of the roast and cover the entire roast.
Bring wrap tightly across the meat and refrigerate for a minimum of 4 hours. I usually marinate roasts overnight. You may add salt if you wish. My habit is to salt meat after it cooks.