Prep your banana. If you like a super thick smoothie, peel and slice a ripe banana and freeze it in a bag for at least 2 hours. If using fresh, just peel and break it into chunks.
Add ingredients to the blender. Banana first, then peanut butter, then milk. This order helps everything blend smoothly.
Blend until creamy. Start on low, then move to high.
Blend about 30–45 seconds, or until completely smooth and frothy.
Adjust texture. Too thick? Add a splash more milk. Too thin?
Toss in a few ice cubes or a bit more banana and blend again.
Taste and tweak. Want it sweeter? Add a touch of honey or maple. Add cinnamon or vanilla if you like a warmer flavor.
Pour and enjoy. Serve immediately for the best taste and texture.