Looking for an eleventh-hour engagement ring in New Orleans? Tommy Aucoin’s your man.1. What was your finest hour in the realm of customer service? A few years ago, a man calls me on Feb. 13, asking if I can make a ring [for his then-girlfriend] in time for Valentine’s Day. My bench ­jewelers said they could hand-fabricate a ring in 24 hours, so I committed to the plan. Although we worked on it the night before, on Valentine’s Day we were slammed, and we ran into unforeseen complications and delays. He did his best to draw out the surprise over dinner, but still no ring. When the ring was ready, I raced across town. It passed from my hand to the restaurant owner’s hands, to the customer’s hand, and onto her finger in minutes—just in time for dessert. To this day, I’ve received about 20 to 25 referrals from this man. 2. What nightmare scenario did you turn around to save th