Step 1: Preheat your oven to 350°F (175°C).
Step 2: Line a muffin tin with paper liners or grease it lightly with cooking spray.
Step 3: In a medium bowl, whisk together the flour, baking powder, baking soda, cinnamon, and salt.
Step 4: In a large mixing bowl, beat the softened butter and sugar together until light and fluffy.
Step 5: Add the eggs one at a time, mixing well after each addition, then stir in the vanilla extract.
Step 6: Mix the mashed bananas, Greek yogurt, and honey into the butter mixture until well combined.
Step 7: Gradually add the dry ingredient mixture to the wet ingredients, stirring gently until just combined.
Step 8: Gently fold in the chopped walnuts.
Step 9: Spoon the muffin batter into the prepared muffin tin, filling each cup about two-thirds full.
Step 10: Place the muffin tin in the preheated oven and bake for 18-20 minutes.
Step 11: Once baked, let the muffins cool in the pan for about 5 minutes before transferring to a wire rack.