Pre-heat oven to 400°
On a large rimmed baking sheet season lamb with salt & pepper.
Rub the Dijon mustard evenly over lamb mostly on the fat side.
Mix all herbs together in a small bowl and gently pat them into the mustard on the fat side of the lamb.
Heat olive oil in a large pan or griddle over medium-high heat.
Sear the rack of lamb, fat side down.
Turn the heat up just a touch right after you place the meat on. The heat will drop when the meat is placed on and to get a good sear it must remain hot.
Cook meat for 2-3 minutes.
Flip lamb over to sear the other side for 1-2 minutes or until browned.
Place meat in the oven fat side up and add rosemary springs on top.
Roast for 15-20 minutes or until meat reaches 140° when temped.
Let meat sit for 5 minutes before cutting.
Slice meat in between the bones into what I like to call 'lamb lollipops'