On a recent morning in Red Hook, Brooklyn, self-styled baker and entrepreneur Kim Ima — better known as the “Treats Truck Lady” — was polishing Sugar.

Sugar is what Ms. Ima calls her retro-style truck, from which she sells cookies, brownies, and other confections all over the city. The baked goods — served with a healthy dollop of good cheer from Ms. Ima — have already developed a devoted following since the Treats Truck first took to the streets in early June.

Most mornings, Ms. Ima, 39, is at her Red Hook bakery at 5 a.m., and she doesn’t get back to her West Village apartment until about 10 p.m. Such long days are the price the actress and director pays to head up a popular mobile pastry outlet.

“A few years back I was baking for the theaters I worked with,” she explained, as she loaded her truck with trays of cookies and other snacks that she and her small staff had prepared earlier that morning. “I’d bake for the cast of a show, and then for a benefit. And then the Treats Truck idea hit me. And I thought, ‘That just sounds like the best idea ever’ — the delight of a little truck that travels around. It came to me fully formed.”

The Treats Truck is an unusually well-conceived brand, from the truck itself, which is festooned with playful slogans and logos (the most clever touch is a “How’s My Baking?” inscription on the back), to Ms. Ima’s red, white, and blue uniform, which evokes a mix of Good Humor man and mid-1960s flight attendant. Toss in the sweets, and it adds up to an irresistibly nostalgic pitch that appeals to people of all ages.

But the key element is Ms. Ima herself. Pint-size with an energy level that would make the Energizer Bunny look like a slacker, she was nearly a blur as she darted to and fro, making her final preparations. “It’s funny, I went from having no car at all to having this,” she said, climbing into Sugar’s cab at about 10:30 a.m.

With that, the woman who just may be New York’s littlest truck driver trundled away from the curb and was off.

By noon, after making a few deliveries, Ms. Ima had set up shop at her location for the day, the southeast corner of Fifth Avenue and 38th Street in Manhattan. Soon, a small crowd of customers — some of whom had been anticipating her arrival, having checked her schedule at www.treatstruck.com — had gathered, and began ordering cookies and Rice Krispies Treats. When the last customer had been served, Ms. Ima hopped out of the truck and stood on the sidewalk offering free samples, drawing another crowd. This process essentially repeated itself for the next several hours.

The area in front of the truck felt like an impromptu party. Mike Mucci, a toy designer biting into a Rice Krispies Treat, summed up the prevailing mood: “This is so much better than running into a bodega and getting something prepackaged. It’s like your mom’s baking stuff for you.”

Of course, none of these good feelings would amount to much if Ms. Ima’s treats weren’t so good. Her brownies ($3) are rich and fudgy (there’s also a raspberry-topped version, which ranks among the best confections in town), her cookies ($1 to $2) strike just the right balance between crisp and chewy, and her Rice Krispies squares ($2) are rich but not heavy — a perfect midday snack. The baking came easily for Ms. Ima; the challenges came from all the ancillary issues. For starters, she wanted an ecologically friendly truck — on eBay, she found one that runs on compressed natural gas — and to customize it for bakery sales. Then, she had to familiarize herself with the maze of official regulations and unofficial protocols governing New York vendors.

“There’s no single source of information or checklist for starting an operation like this,” Ms. Ima said. “Besides all the paperwork and parking restrictions, you don’t want to be parked in front of someone’s café, or near another vendor. Luckily, lots of ice cream truck guys and other vendors have taken me under their wing, and kept an eye out for me because there are certain things you can’t learn until you’re out on the street.”

As for the future, Ms. Ima envisions a storefront retail bakery, called the Treats Truck Stop and, perhaps, a small fleet of additional trucks, each with its own uniformed driver.

For now, she’s just enjoying being the Treats Truck Lady — a role she said feels like the culmination of all her years as an actress. “One thing I loved about theater is the interaction with people, and this is very similar in that regard,” she said. “It combines all of my skills.”