1. Comenico Lab
Get the rice-flour chiffon cakes, the shop's whole reason to exist, in whatever flavors are stocked. Light, plain, and safe, near Tokyo Skytree.
Comenico Lab is a dedicated rice-flour maker with its own production kitchen, so the chiffon is built without wheat. It is a factory-direct shop in Oshiage with limited days, roughly closed midweek and Sundays, so check before heading over. If you are highly sensitive, confirm the current setup at the counter, since the paper trail is lighter than the top picks.