Before starting, you should preheat your oven to 350°F (180°C) and get a 12-cup muffin pan ready. This recipe produces muffins that are naturally a bit sticky, so you should lightly oil the paper liners to prevent issues. Alternatively, you can skip the liners entirely and oil a non-stick muffin tin well, ensuring the baked muffins release with ease.
In a large bowl, peel and thoroughly mash the bananas. After this, To the mashed bananas, add the egg, Greek yogurt, honey, and vanilla. Whisk the mixture until it appears smooth and creamy.
Add the flour, oats, baking powder, baking soda, cinnamon, and salt into the bowl. Use a spoon to stir gently, stopping once you no longer see dry flour. Overmixing will prevent the muffins from remaining soft and tender.
Add the blueberries and give the batter a quick, gentle stir.This helps keep the berries whole and evenly spread, which is key for soft blueberry muffins.
When scooping the batter into the muffin liners, you fill them all the way to the top. Filling them to this level is a process that creates the tall, bakery-style blueberry oatmeal muffins.
You bake the muffins for 22 minutes. You continue baking them until the tops are set and they appear lightly golden. After baking, you let the muffins cool in the pan for 5 minutes. You then move them to a rack. You allow them to cool fully before you start peeling the liners.