Preheat your oven to 350 degrees Fahrenheit (175 degrees Celsius) and prepare a 12-cup muffin tin by lining it with paper liners.
In a large bowl, mash the bananas well.
Add the sugar, eggs, oil, milk, and vanilla and whisk well to combine.
Add the flour, baking soda, and salt. Add the blueberries on top of the flour and toss the berries just a little bit in the dry ingredients before combining everything together gently with a silicone spatula just until the flour disappears.
Divide the batter between the muffin cups until they're about 3/4 full.
Bake for about 19-23 minutes until the muffins are golden brown on top.
Let the muffins cool in their tins for several minutes before removing them to a wire rack to finish cooling completely.
Notes
Storage Instructions
These muffins keep well in an airtight container for up to 3 days
Freezer Instructions
Freeze these muffins in an airtight container or freezer bag for up to 3 months.
No-Fail Tips
If using frozen berries (not recommended), mix the dry ingredients in a separate bowl and combine the frozen berries with the flour mixture, making sure they're very well coated in the flour. Then combine the wet and dry ingredients. This will prevent the frozen berries from colouring the batter.