It’s 2 a.m. in Lake Worth and the kid in front of us is struggling to find the rest of the money for the $5 hot dog from PS 561, the school-bus yellow food wagon, which is parked outside the Speakeasy Lounge.

Nearby, a group of barflies are taking a break from the Speakeasy’s entertainment – tonight it’s a Beach Blanket Bash, featuring special swimsuit models. After watching the kid rifle through his pockets again, owner Aaron Merullo good-naturedly spots him the rest of his hot dog. The kid in cami shorts happily disappears into the night, munching his dog as he goes.

A girl leaves the Speakeasy swinging a hula hoop as she walks down the street. Meanwhile, I’m trying to decide what hot dog to order at the PS 561 window. Do I want the very popular Principal Ron (goat cheese, bacon and BBQ sauce) or the Crazy Art School Teacher (extra BBQ sauce, jalapeños, cheddar and frito chips)?

Merullo, who is truthfully not a late-night person, works as a waiter on the weekend, then takes his banana-colored hot dog truck out to food truck rallies and different bars around Lake Worth and West Palm Beach – find his schedule on Facebook and Twitter – sometimes serving his inventive and delicious dogs until 6 a.m.

“It’s street food, but it’s perfect late-night food,” Merullo says. “The bars love it, because it keeps people here. It’s great if you’ve had a few too many; it will fill you up.”

Merullo, at his core another foodie who frequents places like Buccan in Palm Beach and Yardbird in Miami, is a lifelong hot dog lover.

“It’s one of my favorite foods. It’s one of the things I’ve perfected since I was a little kid. And it’s simple. Simple, simple, simple,” he says.

And delicious.

The Crazy Art School Teacher is the perfect amount of spicy, zesty and filling — and I’m seriously considering buying another before I leave.

THE INFO: PS 561, which opened about a year ago, serves hot dogs four to five days a week. Find the truck’s menu and schedule at ps561.com, Twitter.com/ps561 or Facebook.com/ps561.