For the Risotto, melt butter in large saucepan on medium heat. Add onion; cook and stir 2 minutes or until softened. Add rice mix; cook and stir 1 minute to toast rice. Add lemon juice and Limoncello liqueur; cook and stir 1 minute or until almost evaporated.
Stirring constantly, add warm stock, 1/2 cup at a time, until liquid is absorbed by rice after each addition. (It takes about 25 minutes for all of the stock to be absorbed and the risotto to become thick and creamy.) Season with pepper.
Meanwhile, for the Lamb Chops, mix lemon thyme, oil, honey, lemon peel, ginger, pepper and sea salt in small bowl until well blended. Rub 1 tablespoon of the seasoning mixture on lamb chops.
Grill lamb over medium heat 10 to 15 minutes per side or until desired doneness. Let stand 10 minutes. Divided arugula among each plate. Top with risotto. Place a lamb chop on each plate. Drizzle with remaining seasoning mixture.