Just One Dish: Samgak Kimbap at Cafe Walnut

The story behind this off-menu Korean rice ball served at a cafe near Washington Square and why you should be going out of your way to eat it.

Samgak kimbap at Cafe Walnut / Photography courtesy of Ashley Lee

Welcome to Just One Dish, a Foobooz series that looks at an outstanding item on a Philly restaurant’s menu — the story behind the dish, how it’s made, and why you should be going out of your way to eat it. 

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Every day, just before noon, Ashley Lee shapes 15 samgak kimbap behind the counter at Cafe Walnut off of Washington Square. Each triangle of rice fits snug in her hand, hiding cores of either spicy tuna, soy-and-gochugaru marinated chicken, or strips of Lee’s mom’s kimchi — fermented long enough so the tang and funk of the cabbage comes through stronger than garlic and heat. And pretty much every day, (other than Sunday when the shop’s hours are limited to mornings only) Cafe Walnut’s batch of samgak kimbap sells out. It’s not even listed on the menu.

When Lee and her two older brothers, Christopher and Daniel, took over the subterranean coffee shop in 2020, they filled the menu with some of the comfort foods they ate growing up in Philly and during the years they spent in Korea as kids. A compact little breakfast sandwich, for instance, that stockpiles spicy-sweet pork bulgogi and scrambled eggs on a croissant, glued together by the sheer will-power and chemistry of glossy, gloppy American cheese and a slap of Sriracha mayo. If there’s a better breakfast sandwich in Philadelphia, I haven’t had it yet. And the bulgogi, egg and cheese isn’t even the most exciting item on Cafe Walnut’s menu.

No, the thing at Cafe Walnut that has me setting a mental alarm clock for Saturdays at noon is a $4 samgak kimbap filled with kimchi — wrapped in a crisp sheet of seaweed, still warm from the rice cooker, nutty and a little sweet from sesame oil, and flecked with black-grain rice that gives the snack subtle pops of crunch and a purplish tint. In the cafe and on Instagram, Lee and her brothers refer to their samgak kimbap as “onigiri,” the Japanese word for the stuffed rice ball, because she tells me it’s easier to say. Regardless of what you call it, each one is sold in a plastic envelope with simple instructions about how to tear open your snack without ripping the seaweed pocket in the process. Right now, the branded plastic wrappers that Cafe Walnut uses include a sticker that reads “happy” in English. Consider this a convenient reminder of the way you’ll feel when you bite into yours.

Samgak kimbap only joined Cafe Walnut’s menu in 2022, two years after the restaurant’s opening. But the idea to serve the rice balls came from the Lee siblings’ mom, who ran the beloved University City food truck KoJa for almost 10 years. As a kid, Ashley would help her mom prep and shape samgak kimbap for the food truck. “Now that we had our own specific spot, we were like ‘Why not just bring it back?’” Ashley says.

For every batch of 15 samgak kimbap, Ashley uses about six or seven cups of short-grain rice. She seasons the rice with sesame oil, a bit of salt, sesame seeds, and a Japanese vinegar powder typically used for sushi rice. Once the rice is cool enough to touch (but not so cold that she can’t manipulate it) she forms each samgak kimbap with a mold: “The mold helps you layer everything. The first layer is the base of the rice and then the second layer is the filling. Then I top it off with more rice and press it down.”

Once each samgak kimbap is ready, they’re placed in a wicker basket by the cash register at Cafe Walnut to attract people who are familiar with the grab-and-go snack, or anyone who wants to try it for the first time. “A lot of times people ask what it is,” Ashley tells me. “When you explain it, people are like ‘Oh this is fun’ or there are people who have traveled to Korea or Japan and have seen it.”

Ashley says she’s only found onigiri or samgak kimbap at the rare establishment in Chinatown, including the boba shop Tea-Do. When she started making her own versions for the cafe, she says it was important to nail the ratio of rice to filling: “When I used to buy it, it would just be a huge ball of rice with very little filling and I’d be so disappointed.”

As for the fillings offered in Cafe Walnut’s samgak kimbap, Lee’s mom still makes all of the kimchi. She originally picked up the recipe from her husband’s mother (Ashley’s grandmother). “Every Korean family’s kimchi is somewhat different. That’s what’s so unique about it,” Ashley says. “It’s just the familiar taste that we’ve been eating since we were kids.” For the samgak kimbap specifically, Lee’s mom ferments her kimchi for longer than she would in other dish contexts.

When Ashley started offering samgak kimbap at Cafe Walnut, she wanted to make limited quantities to see the response from customers. Now that the rice balls have been selling out, she says she’s open to offering more than 15 per day: “This is what we ate growing up. We wanted to push that to other people who have never tried it or maybe haven’t seen it around. It’s just a nice snack to eat.” If you want to get in on the snacking, stop by right around noon any day from Monday to Saturday.

So much of the food we eat when we go out prides itself on being complicated. Cafe Walnut’s samgak kimbap is proof that a simple snack, when done thoughtfully, can be the thing you daydream about all week. No meat required.