Blend everything — add bananas, milk, and cocoa powder to a blender. Blend on high for 60 seconds until completely smooth and silky. For an extra smooth result, strain through a fine sieve.
Cook on medium heat — pour the mixture into a saucepan. Stir continuously for 5–8 minutes until the mixture thickens noticeably. Don’t stop stirring or it will catch on the bottom.
Pour into a greased silicone mold or lined baking dish. Smooth the surface with a spatula. Tap gently on the counter to remove air bubbles.
Refrigerate for at least 4 hours or overnight until completely set and firm throughout.
Invert onto a serving plate. Peel away the mold or paper slowly. Add toppings. Try not to cry at how beautiful it looks.
