Sprinkle lamb with steak seasoning. In a large skillet over medium-high heat, cook lamb in oil for 2 minutes on each side. Brush with mustard.
In a small bowl, combine the panko, thyme, mint, Worcestershire sauce and rosemary; press onto lamb. Transfer to a greased 15-in. x 10-in. baking pan. Bake, uncovered, at 375° for 15-20 minutes or until meat reaches desired doneness (for medium-rare, a meat thermometer should read 145°; medium, 160°; well-done, 170°).
In a large skillet, saute mushrooms in oil and 2 tablespoons butter until tender. Add garlic; cook 1 minute longer. Stir in wine. Bring to a boil; cook until liquid is reduced by half. Remove from the heat. Stir in the broth, honey, remaining butter and chives if desired.
Remove lamb from oven and loosely cover with foil. Let stand for 5 minutes before slicing. Serve with sauce. Yield: 4 servings (1 cup sauce).