Inspired by French tradition, this rack of lamb is encrusted with a mixture of Dijon mustard, breadcrumbs, parsley, thyme, and rosemary. It's served family style on a bed of minted fava beans.
Combine breadcrumbs, 1 teaspoon mustard, parsley, thyme, rosemary, and 1 tablespoon olive oil in a small bowl. Mix well with a fork; season with 1/2 teaspoon salt and 1/4 teaspoon pepper. Set aside.
Preheat oven to 375 degrees. In a large skillet, heat 1 1/2 tablespoons olive oil over medium-high heat. Sprinkle lamb with 1 teaspoon salt and 1/2 teaspoon pepper; place in pan, and sear on all sides, 4 to 5 minutes total, reducing heat if oil begins to smoke. Transfer lamb to a small roasting pan, reserving skillet with oil.
Brush lamb with remaining 2 tablespoons mustard; press breadcrumb mixture on all sides until completely covered. Roast in oven 35 to 40 minutes, or until a meat thermometer inserted into thickest part registers 155 degrees. Remove from oven; let rest 5 minutes before serving.
While lamb is cooking, heat reserved skillet with oil over medium heat. Add shallots, and saute until they begin to soften, about 30 seconds. Add fava beans, and season with remaining 1/2 teaspoon salt and 1/4 teaspoon pepper. Cover; cook until beans are tender, about 3 minutes.
Just before serving, stir in mint, marjoram, and lemon juice. Serve bean mixture as a bed for the lamb on a serving platter.