Combine dry ingredients. In a mixing bowl, whisk together flour, brown sugar, salt, baking powder, and cinnamon. Fold in chocolate chunks. 2 cups (240 g) all purpose flour 1 cup (213 g) packed light brown sugar ½ teaspoon salt 1 tablespoon baking powder 1 teaspoon ground cinnamon 1 cup (170 g) chocolate chunks
Combine wet ingredients. In a second mixing bowl, add the bananas to the bowl and mash with a fork. Add in the eggs, oil, milk, vanilla extract and whisk to combine. 2 cups (480 g) mashed bananas (about 4 large) 2 large eggs ½ cup (120 mL) neutral-tasting oil 2 teaspoons vanilla extract 6 tablespoons milk
Combine wet and dry ingredients. Add the dry ingredients to the wet ingredients and mix together with a spatula until just combined.
Let the batter rest. For the best results I like to let the batter rest for an hour (this results in a taller muffins).
Preheat and prepare pan. Preheat oven to 400°F (205℃). Line two muffin tins with alternately paper liners, or grease with non-stick cooking spray. I line the pan with only 6 liners each (skipping every other well). This makes for taller muffins.
Bake. Divide batter into prepared muffin cups, filling each well to the top and bake for about 20 minutes until a toothpick inserted in the center of the muffin comes out clean. Remove from the oven and allow the muffins to cool completely in the pan for about 5 minutes, then remove from the pan and continue cooling on a wire cooling rack.