Add the sliced bananas, peanut butter, milk, and honey to the blender.
Secure the lid and blend on high speed until the mixture is smooth and creamy, about 30-45 seconds. The smoothie should be thick, frothy, and well combined.
Check the texture — if it’s too thick, add a splash more milk and blend briefly to loosen.
Pour the smoothie into glasses, watching it flow in a smooth, velvety stream with a rich, nutty aroma.
Serve immediately for the best flavor and texture, garnished with a slice of banana or a drizzle of honey if desired.