Umami Kushi’s potato chips emit an unreasonably satisfying crunch as gently explosive as their curry chicken flavor—seemingly lab-designed to pair with local IPA. Which they kind of are: when Harold Fields, the Rainier Beach okazu pan specialist, set up a kiosk inside Métier Brewing Company’s taproom, he got to work developing a savory snack that customers could grab quickly.

Umami Kushi’s stuffed buns combine the culinary techniques and flavors Fields learned eating and training in Japan with those he knew from living in New Orleans. As he set out to translate that combination into a potato chip, he used the beer-drinking adults and their taproom tots at Métier as a test audience.

To make a potato chip with the heft and crunch Fields found missing from most commercial versions, he and his team hand-slice 75 pounds of Washington potatoes at a time, then use a cold-water washing process to help them stay crispy through frying. This is one of a few steps that give them their impressive crunch, but it’s the only one he’s willing to share.

Fields dusts the chips with a seasoning that shares some similarities with the spice mixes he uses in his Japanese stuffed breads. He tweaked it based on his testers’ reactions until it had just the right punch to match the chips’ bold texture. When he created his first flavor, the kids at Métier had feedback. “In the beginning it was true Caribbean jerk seasoning, it was spicy, it had bite to it,” Fields says. But the response from families encouraged him to tone it down. He followed that up with the curry chicken, using Japanese curry powder and dried chicken. For now, the two-ounce bags ($5) are sold mainly at Umami Kushi’s two locations and a few other local breweries. Fields hopes to expand that roster in the future, but don’t expect to see them on grocery store shelves anytime soon—he doesn’t need testers to understand that the freshness plays a big part in what makes the chips so good.

Expanding to grocery stores would require a longer lead time and potentially adding stabilizers. Instead, Fields plans to stay focused on cooking up the crispest chip he can and adding flavors, depending on what he hears from his de facto focus group. “Seattle is a beer town,” says Fields. “Where I see success is the breweries, it’s a lot of the local places.” To him, this remains primarily a drinking snack, and the opinions that matter most come from his taproom testers.