Preheat your oven to 350°F (175°C) and grease a mini muffin tin or line it with mini muffin liners
In a mixing bowl, mash the ripe banana until smooth
Add the yogurt, egg, applesauce, and vanilla extract to the mashed banana and mix until well combined
Add the flour, baking soda, baking powder, and salt and mix until just combined
Spoon the batter into the prepared mini muffin tin, filling each cup about two-thirds full
Bake in the preheated oven for 10-13 minutes, or until the muffins are golden brown on top and a toothpick inserted into the center comes out clean
Allow the muffins to cool in the tin for a few minutes, then transfer them to a wire rack to cool completely
Serve and enjoy!