"I'm not vegetarian," says Eric, owner of MF Tasty. "But I wanted the mushroom cemita to be so good that I'd want to eat it."
His outlet is, like so many in Portland, a kitchen on wheels. Food cart MF Tasty serves just two types of cemita, a Mexican snack involving a sesame seed bun: one filled with achiote-glazed pork, the other with Korean barbecue marinated mushrooms.
As promised, the mushroom version is delicious.
I shouldn't be eating before I join a food tour, but it's hard to resist the highly diverse output of Portland, Oregon's food cart scene.
"Pods" of these carts can be vast, such as the 60 or so at the intersection of SW 9th Avenue and Alder in the city's Downtown. Or as humble as this pod off North Mississippi Avenue in North Portland, with four carts and picnic seating.
Both carts and restaurants are included in the Forktown food walking tour of North Mississippi Avenue, an easy-going shopping street.
"This is not a white tablecloth neighbourhood," says our guide Ariel, artist by day and waitress by night. "This tour fits that profile."
After eating servings of the Thai glass noodle salad yum woo sen at Mee Sen (coincidentally opposite the art gallery featured in the "Put a bird on it" sketch on TV show Portlandia), we drop into Little Big Burger.
A small local chain, it makes just three burgers along with truffle fries. It's a case of less is more, with its cheeseburgers featuring local beef and a choice of cheddar, Swiss, chevre, pepperjack or blue cheese, for a mere $4.25.
Next stop is Sidecar 11, a bar inside an old house opened up to the rafters. The menu features 1920s-inspired cocktails, but I try the Fall Mule, a Moscow Mule variant with gin, pineapple sage, cucumber, ginger puree and ginger beer.
Moving on, we sample piadinas from food cart Gabagool, and Madagascar chocolate and international salts at The Meadow. Dessert is at Ruby Jewel, a choice of excellent ice-cream sandwiches: double-chocolate cookie with salted caramel ice-cream, or lemon cookie with honey lavender ice-cream.
Interestingly, Ruby Jewel started out as a farmers' market stall and morphed into a regular store, demonstrating the cart and stall's valuable role in experimentation.
On my last day in the city I join another tour, this one focusing on coffee at establishments like Case Study (which is popular enough to have three locations). It's easy for an Australian to be dismissive of American coffee, but in Portland there is a genuine quality coffee scene.
Case Study, various locations, casestudycoffee.com.
Gabagool, 3710 North Mississippi Avenue, Portland, gabagoolpdx.com
Little Big Burger, various locations, littlebigburger.com
The Meadow, various locations, themeadow.com
Mee Sen, 3924 North Mississippi Avenue, Portland, meesenpdx.com