Preheat your oven to 350°F (175°C). Grease a 24-cup mini muffin pan with non-stick cooking spray or line with silicone mini muffin liners.
In a large mixing bowl, mash the peeled bananas with a fork until smooth.
Whisk in the egg, Greek yogurt, pure maple syrup, melted coconut oil, and vanilla extract until the wet mixture is smooth and fully combined.
Sprinkle the white whole wheat flour, baking soda, ground cinnamon, and sea salt directly over the wet ingredients.
Using a spatula, gently fold the dry ingredients into the wet batter just until the flour disappears. Do not overmix. Fold in mini chocolate chips if using.
Divide the batter evenly among the 24 mini muffin cups, filling each cup approximately 3/4 full.
Bake at 350°F (175°C) for 12 to 14 minutes, or until the muffin tops are golden and a toothpick inserted into the center comes out clean.
Allow the muffins to cool in the pan for 5 minutes, then transfer them to a wire cooling rack to cool completely.