01 - Place the frozen banana slices in a high-powered blender or food processor.
02 - Add protein powder, peanut butter, cocoa powder, vanilla extract, and 2 tablespoons almond milk to the blender.
03 - Blend on high speed, stopping occasionally to scrape down the sides. Continue until completely smooth and creamy. Add additional almond milk one tablespoon at a time only if the mixture is too thick to blend properly.
04 - Taste the mixture and adjust sweetness or cocoa intensity according to personal preference.
05 - Serve immediately for a soft-serve consistency, or transfer to a freezer-safe container and freeze for 1-2 hours to achieve a firmer, scoopable texture.
06 - Top with chopped roasted peanuts and dark chocolate chips if using. Serve chilled.