Matcha soft serve
The most visible form of matcha in Osaka's tourist districts is soft-serve ice cream — intensely green, varying wildly in actual matcha quality between chains. The best indicators of a worthwhile one: a bitter, vegetal finish rather than just sweetness, and a queue of people who aren't carrying cameras.
Matcha in cafes
Osaka's cafe scene has followed the nationwide trend toward matcha lattes, matcha parfaits and matcha-based wagashi, with everything from specialist tea rooms in Namba and Umeda to convenience-store canned matcha lattes that are, genuinely, quite good. Department store basement food halls (depachika) are the most reliable places to find high-quality wagashi with matcha fillings.
For the serious stuff: a day trip to Uji
If matcha is the main point rather than a pleasant detour, a day trip to Uji — between Osaka and Kyoto — puts you in one of Japan's oldest and most respected matcha-growing regions, with tea shops and fresh-ground options unavailable in the city.