Luis Diaz built the bus, naming it La Promesa, shortly after he moved with his family from Puerto Rico to Wisconsin, he told Patch. Diaz found the vehicle for sale one day on Craigslist, and after building it out since 2021, the spot opened for business in May, he said.
You can find the bus parked at 21300 West Greenfield Avenue in New Berlin on Thursdays, Fridays and Saturdays from 11 a.m.-8 p.m., but Diaz said he also plans on visiting festivals and food truck events in the future.
“Nobody has a food truck with tables inside and a kitchen,” Diaz said. “So that was my goal, to surprise people, to make them to come and enjoy the food at the same time and they can relax like a restaurant, but in a bus.”
When Diaz first came to the Milwaukee area with his family, they found a lack of Puerto Rican food in the area. He tried things around the Milwaukee area, but it wasn’t quite cutting it. So Diaz told his wife about the bus idea.
“We need to make this, we need to do it,” Diaz said he told his wife. “Because I know people are going to come over, it doesn’t matter if we are 15, 20 minutes away or 30, we’re making this because they don’t have nothing around.”
La Promesa’s menu is small, Diaz said. He made it simple as he hopes people will try more than one thing.
“I want people to know what we offer in Puerto Rico,” Diaz said.
What To Try At La Promesa
For someone unacquainted with food from Puerto Rico, Diaz recommended trying a few things, but especially the carne frita con chimi y tostones: a dish consisting of soft, deep-fried Chimi pork with fried flat plantains.
“The tostones with garlic butter,” Diaz said. “Oh man, it’s another level.”
Diaz also recommended the camarones shrimp, which are pan-fried garlic shrimps served in a white sauce with plantains; or street-food staples like bacalaito or alcapurrios.
Bacalaito consists of battered and deep-fried cod fritters with traditional seasoning. Alacapurrios are a type of fritter as well — Diaz places ground beef into a dough made out of plantains and deep-fries it.
Another street-food recommendation from Diaz was the pinchos de pollo, a type of chicken kabob.