Preheat oven to 350°F and coat a mini muffin pan with non-stick cooking spray.
In a medium bowl, combine rolled oats, cinnamon, nutmeg, sea salt, bananas, eggs, milk, maple syrup, and vanilla extract.
Add in frozen berries and mix everything together.
Scoop the muffin mixture into the mini muffin pan and place in the oven. Bake for 18-20 minutes or until tops are slightly golden. Remove from oven and let cool for 10 minutes. Using a butter knife, go along the edges of the muffin to help loosen it - they should pop out easily at this point.
Recipe Notes:
If you’re using a regular-sized muffin pan you can bake for approx 23-25 minutes instead.