Sawawa is a Kawagoe matcha green tea store and cafe. It is set up mostly for take away, but there are a few seats at the back of the store. It is easily identifiable by the green tea grinding mill outside the shop, and there is also a large green ice-cream cone by the door.
Sawawa is one of several stores by Telacoya, who specialize in Japanese souvenirs. The store part of the shop has various different matcha green tea flavored products for sale. You can buy nicely wrapped dango, baumkuchen, candy, pudding, and macaroons - all matcha flavored - to name but a few. Several of the products have samples available so you can taste the product before buying. They also sell matcha and green tea leaves. The kiosk sells such things as matcha flavored ice-cream and matcha or green tea flavored drinks. One of their most popular foods is the Kawagoe Matcha Warabi-Mochi, a type of Japanese hard jelly.
Sawawa is open from 10 am to 6 pm seven days a week. Please do check with the official website for the latest updates. The Telacoya company also has an English website. It doesn't detail Sawawa in particular, more general information about the company, but they do list all of the branches around Japan in English.