Every Thursday night, Lonnie Bishop and Lisa Case have a dinner date. For $5 each, the couple dines on fancy hot dogs served from a food truck parked outside their favorite wine shop in Los Angeles.

The fire engine-red truck labeled Let's be Frank is part of a growing fleet of mobile food vendors that serve tasty and inventive fare, often organic.

The trend has drawn entrepreneurs looking for opportunities in the recession and diners seeking cheap eats.

The new vehicles raise the bar from the traditional taco trucks that sell mainly Mexican fare at construction sites and in neighborhoods in U.S. cities with big Latino populations.

Their menus are wildly different, attracting adventurous foodies with unusual items: tacos filled with Korean-style barbecued meat, vegan burgers, sushi, cupcakes, and architecturally inspired ice cream sandwiches.

I've eaten all over the world in three-star restaurants. I enjoy this as much as I enjoy anything and I save a lot of money, said Bishop, 46, holding a bun-wrapped sausage made from family-farmed pork and topped with pickles.

With the economic downturn, restaurateurs have struggled to find funding to open full-scale restaurants, said Tom Forte, an analyst at Telsey Advisory Group in New York City.

The cost of setting up an eatery on wheels is a fraction of what's needed to open a sit-down restaurant, Forte said, noting it takes $900,000 to open a Chipotle Mexican Grill.

Erica Cohen, 34, began her career at an upscale restaurant group but scaled down her dream of opening a traditional burger joint because it seemed so risky during the recession.

So, for $30,000, Cohen and her business partner leased a boxy truck complete with a kitchen and an order window.

BURGERS AND TRUFFLES

Their hot pink truck, called Baby's Badass Burgers, flaunts a logo of two buxom cooks who could double as pin-up models and sells gourmet mini-burgers. Parked off Hollywood Boulevard, the truck draws workers like Lara Yturriaga, who ordered a Cougar -- two mini burgers topped with St-Andre cheese and black truffles.

I'm on a quest this whole month (to eat at) 10 food trucks, Yturriaga, 25, said. So far, she's tasted Indian crepes and Asian-style meat in a rice-patty bun.

I like that it's always something different, she said.

Many operators use Twitter to tell customers where they're going next. 'Kogi,' which serves Korean barbecue tacos, was among the first to use the free social media site.

A restaurant is more like a passive sell. The lunch truck is more active, said Takeshi Kimura, who launched his Fish Lips sushi truck this summer.

Big chains are putting their own spin on the trend.

Taco Bell, owned by the giant Yum Brands Inc, uses Twitter for its promotional taco truck that hit the road this summer, handing out free food along its cross-country route.

Diner Michelle Madrid, 26, said the fun is in the chase.

It's cool -- the whole 'guess where we are,' she said.

Plus, it's now hip to be a penny-pincher.

It used to be cool to have a credit card and be all high-flying. Now cash is king, said Kam Miceli, who helped start Green Truck, which serves high-end organic fare.

Miceli, who built up a fleet of 11 trucks in Los Angeles and New York, plans to expand in Miami in the fall and is eyeing markets like Austin, Texas, and Washington, D.C. While developers have tried to convince him to open a traditional sit-down eatery, Miceli says he is not interested.

We are sticking with trucks, he said.

(Editing by Alan Elsner, Eric Walsh and Mary Milliken)