Prepare the Ingredients: Slice the banana if using fresh, or use frozen chunks for a thicker smoothie. Measure out the Greek yogurt, milk, and peanut butter.
Combine in Blender: Add all ingredients to a blender, starting with the milk to ensure a smooth blend.
Blend Until Creamy: Blend on high for about 30-60 seconds, or until the mixture is smooth and creamy. Add more milk if you prefer a thinner consistency.
Taste and Adjust: Taste the smoothie and, if desired, add the optional honey for extra sweetness. Blend again briefly to combine.
Serve and Enjoy: Pour the smoothie into a glass and enjoy immediately. You can garnish with a sprinkle of cinnamon, a drizzle of peanut butter, or even a few banana slices for extra flair.