At Albuquerque's Le Cafe Miche, a teenage boy and his girlfriend enjoyed a fancy Valentine's Day dinner. But when the check came, the teenage Don Juan realized he was $40 short.

This was in the late '90s.

The boy spoke to the restaurant's owner and chef, Claus Hjortkjaer. The kind Chef Claus took pity on the young man and gave him $40 from his own pocket. The boy paid his tab and left. Hjortkjaer never saw him again. Until now.

Last week, the mysterious diner returned to Hjortkjaer's newly reopened restaurant to pay off the debt—with interest. KOAT.com reports that the man walked in, asked to speak to Hjortkjaer, explained who he was and gave the generous chef a $100 bill.

"Sometimes it pays off to be a nice guy," Hjortkjaer told KOAT.com. "It made me feel good. I went and bought myself a bouquet of flowers."

Hjortkjaer never got the man's name, but the chef told KOAT.com he's welcome back to the restaurant for a glass of wine, on the house.