Step 1

Preheat oven to 350°F / 175°C. Line or lightly grease a standard 12-hole muffin tin.

Step 2

In a medium bowl, mix together the mashed bananas, milk, cooking oil, vanilla extract and brown sugar. You can mix this by hand, or use a hand mixer on low speed. I usually use a hand mixer since I find that it quickly will mash/puree a ripe banana.

Step 3

In a separate large bowl, whisk together the flour, oats, baking powder, baking soda, cinnamon and salt.

Step 4

Add the wet ingredients into the dry ingredients and mix together until just combined. Stir in the vinegar.

Step 5

Divide batter evenly among the muffin cups. Top the muffins with the oats and turbinado sugar.

Step 6

Bake muffins, rotating pan halfway through, until a tester inserted into the center comes out clean, 25–30 minutes. Transfer pan to a wire rack and let muffins cool in pan 5 minutes. Transfer muffins onto a rack and let cool completely.