1. Preheat oven to 375 degrees.
2. Pat the lamb dry and season liberally with salt and pepper.
3. Heat 1 tablespoon olive oil in a skillet over medium-high heat until shimmering. Add the lamb loins and sear for 45 to 60 seconds on each side. Transfer to a roasting pan and let cool for 5 to 10 minutes.
4. Meanwhile, combine the remaining olive oil, bread crumbs, rosemary and garlic powder in a small bowl. Rub the lamb generously with the mixture.
5. Roast in oven for 20 to 25 minutes, until lamb reaches desired temperature (145 degrees for medium rare, 160 for medium).
6. Transfer lamb to a cutting board and tent loosely with foil. Let rest 10 to 15 minutes before carving into 1/2-inch thick slices.