Preheat your oven to 350°F (175°C) to ensure even baking.
Line a 12-cup muffin tin with parchment paper liners or lightly spray with cooking spray to prevent sticking.
In a large mixing bowl, mash the ripe bananas until smooth for natural sweetness and moisture.
Add vanilla Greek yogurt, milk, peanut butter, melted butter, vanilla extract, and egg to the mashed bananas. Whisk until well combined.
In a medium bowl, whisk together white whole wheat flour, rolled oats, sugar, baking powder, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, stirring gently with a spatula until just combined. Do not overmix; some lumps are fine.
Fold in the white chocolate chips evenly throughout the batter.
Spoon the batter into the prepared muffin cups, filling each about two-thirds full to allow rising.
Bake in the preheated oven for 18-20 minutes, or until a toothpick inserted in the center comes out clean.
Remove muffins from the oven and cool in the tin for a few minutes, then transfer to a wire rack to cool completely. Enjoy warm or at room temperature!