The culinary team behind Ganko Ittetsu Ramen in the Coolidge Corner Arcade has opened up a sister restaurant − right across the arcade aisle. Gantetsu-Ya specializes in Japanese street food with an emphasis on takoyaki, doughy balls filled with octopus.

Chef Ken Iwaoka was born and raised in Tokyo and immigrated to the United States as a teenager. Dishes he loved in his childhood inspired the restaurant concept. "When you're a kid, that's the stuff that after school my mother would make me," says Iwaoka. "I want to showcase something that I grew up with, and this is becoming popular."

Gantetsu-Ya opened in September, and Iawoka says they're taking their time growing a customer base to perfect the dishes. Many of the diners come from Ganko Ittetsu Ramen for quick bites before or after their other meal. In that way, the dual restaurants' situation across from each other work well in tandem.

On the menu, you'll find the takoyaki balls, traditionally stuffed with octopus, tempura scraps, pickled ginger, and green onion. You'll also find okonomiyaki, a savory Japanese pancake typically filled with vegetables and meats. Iawoka compares the okonomiyaki to pizza in that you can use many different ingredients (toppings, if you will) to make the dish in various ways. He plans to swap out the ingredients with some regularity. The menu is small by design; Iawoka says he wanted both restaurants to specialize in one area of Japanese cuisine and to do it really well, rather than offering a spectrum of less perfected options. Brookline is evolving into a haven of Asian flavors, and Iawoka says his customers are highly educated about the cuisine. "A lot of customers have true knowledge of Japanese food. They have more interest; they spend more time, they try out new things," he says. "People have experience being in Japan for vacation or business or school, and then they come to us and say 'oh wow, this is the closest thing I can find in America.'"

Smart customers aren't the only reason Iwaoka chose Brookline for the two restaurants. For many years he lived in the area himself and grew to love the balance of neighborhood community and urban access. "My feeling about doing a Japanese restaurant is that we should try to specialize in one thing and be good at," says Iwaoka. "That's our goal, to try to be as authentic as possible."