Hazelnut-Crusted Racks of Lamb with Tomato-Olive Ragoût

Prepare lamb:

Mix 1 cup oil, rosemary and garlic in 13 x 9 x 2-inch glass baking dish. Sprinkle lamb with salt and pepper. Add to marinade; turn to coat on all sides. Cover and chill overnight, turning occasionally.

Grind bread in processor until small crumbs form. Combine 2 cups crumbs (reserve and remaining crumbs for another use), parsley, nuts and shallots in processor. Process until nuts are finely ground. Gradually add 2 tablespoons oil; process until crumbs begin to stick together. Transfer to bowl. Season with salt and pepper. Add 1 tablespoon oil toss gently to coat. (Coating can made 1 day ahead. Cover, chill.)

Make tomato-olive ragout:

Heat olive oil in heavy large skillet over medium-low heat. Add onions, garlic and dried red pepper. Sauté 5 minutes. Add fennel and sauté until translucent, about 3 minutes. Add tomatoes with their juices and olives. Increase heat and bring to gentle boil. Cook until onions are tender and juices thicken, stirring occasionally and breaking up tomatoes with spoon, about 18 minutes. (Can be prepared 1 day ahead. Cover, chill. Rewarm over medium heat before continuing.)

Final preparation:

Preheat oven to 400°F. Heat heavy large skillet over high heat. Remove lamb from marinade. Add lamb to skillet with some marinade still coating lamb. Cook until brown, about 4 minutes per side. (If necessary, brown 1 rack at a time.) Using tongs, transfer lamb to baking sheet; cool 15 minutes. Spread 1 1/2 tablespoons mustard over rounded side of each rack; firmly press half of breadcrumb coating into mustard on each rack.

Roast lamb until meat thermometer inserted into center of lamb registers 135°F for medium-rare, about 25 minutes. Let lamb rest 15 minutes.

Meanwhile, mix basil and butter into warm ragout; stir until butter melts. Season to taste with salt and pepper.

Transfer lamb to cutting board. Cut lamb between bones into individual chops. Divide chops among 4 plates. Spoon ragout alongside chops and serve.