In a small bowl, sift the matcha powder. Add sugar and hot water. Whisk until combine with no lumps. This is where you should taste your mixture and adjust the preferred sugar level.
In another bowl, pour the matcha mixture through a sieve. Add oat milk. Mix until combine.
Add 2-3 pieces of mochi into the popsicle mold. Try to evenly them across the entire popsicle. If you are using regular size popsicle molds, you might want to add more (at least 10 pieces). Add in popsicle sticks.
Fill the popsicle mold 3/4 full with matcha oat milk (don’t throw away the leftover milk). Put in the freezer for at least 30 minutes.
Once the surface of the popsicles is frozen, you can add another 2-3 pieces of mochi to each one. Fill the mold with more matcha oat milk.
Freeze overnight and remove the popsicles from the mold. Ready to serve.