Pour the sweetened condensed milk into the coffee and stir until thoroughly combined. Sift cocoa powder over the top and stir until combined. I found this part a bit tricky because the cocoa powder kept clumping up! Taste the mixture and add more milk or cocoa, depending on your taste. I didn’t need to add any extra.

Pour into molds, as per the instructions for the Zoku, and wait up to 10 minutes to freeze (or just simply pour into plain old popsicle molds and freeze overnight).