Mullen soon found employment as a waiter at Josie's organic restaurant, where he stayed for about five months, earning up to $1,000 a week. But Mullen, who once aspired to be a women's fashion designer, was interested in finding a restaurant gig in the Meatpacking District, a fashionable Manhattan neighborhood.
While applying for a job at a popular New York City club, Lotus, Mullen's style caught the attention of the restaurant's managers, who were about to open a new restaurant in the neighborhood.
Mullen was hired as a waiter when Los Dados opened in the summer of 2007, earning only $150 a night, at first.
"I started coming to work really early," he said. "People thought I was crazy when I'd pick up everybody's shifts, work seven days a week. But at the same time, I was shopping and I was having fun."
In May, Mullen was offered a position as the restaurant's manager. To be a good manager, Mullen said he hired a new slate of servers, played to the strengths of individual workers and created "a new positive energy" among his staff.
"I've just been mixing the elements and making sure I come up with the right equation and treat people the way I want to be treated, especially guests," Mullen said. "I feel like you should go all out for the customer, treat them as if they're in your home."
As hard economic times have forced many Americans to cut back on eating out, Los Dados was worst hit by the recession this past winter.
"It was bad. Everyone was scrambling for shifts. We had only a skeleton staff," said Mullen, then a waiter.
When business was good, Mullen earned between $900 and $1,000 a week as a waiter. As one of six servers, Mullen earned between $400 and $500 a week during the restaurant's lowest point in February, though he said business began to pick up in March.
Business really took off in the summer after the opening of the nearby High Line, an elevated strip in the neighborhood that has been converted into a park. Since its opening, business at Los Dados has tripled, he said.
"We have regular clientele from Columbia University, neighborhood people, movie producers. The whole set of 'Gossip Girls' came in once. There are people like myself," Mullen said of the restaurant's customers. "It's a place where everyone comes to relax, to have a great Los Dados hibiscus blueberry margarita."
Mullen now plans to one day open his own Cajun-style restaurant in the city. He said the menu would include a Cajun-crusted sea bass dish, jambalaya, an entree-sized bowl of Creole gumbo and other New Orleans staples.
"I want to see my vision unfold," he said. "I want to make one, write it down, plan it out and see it implemented."
Mullen's post-Katrina experience is different from that of many evacuees, many of whom have returned to New Orleans.
Four years after the storm, remnants of Katrina's damage still can be seen along the Gulf Coast and in the lives of hurricane evacuees.
"Recovery takes a long time," said Christina Stephens, a spokeswoman for the Louisiana Recovery Association. "We're four years into what will ultimately take 10 to 15 years to do correctly. Every day, it gets a little easier. Every year we have more things to point to, but we still have challenges."
As of June 2009, the Department of Housing and Urban Development had provided $4.4 million in relocation assistance to 5,050 displaced families living in public housing.