Freeze the bananas. Peel, slice into coins, and freeze in a single layer for at least 2–3 hours (overnight is best).
Add to blender. Place frozen banana slices in a high-speed blender or food processor. Add protein powder, vanilla, and a pinch of salt.
Start blending. Pulse to break up the bananas.
Add 2 tablespoons of milk to help the blades catch. Scrape down the sides as needed.
Adjust texture. If it’s too thick to blend, add milk 1 tablespoon at a time. Aim for thick, soft-serve consistency.
Flavor it. Blend in cocoa powder for chocolate, or peanut butter for a nutty version.
Keep blending until silky and smooth.
Serve soft or firm up. Enjoy right away for soft-serve. For scoopable ice cream, transfer to a container and freeze 45–90 minutes.
Top and enjoy. Finish with sliced bananas, nuts, a drizzle of nut butter, or a sprinkle of cocoa nibs.