Add the eggs, vegetable oil, and brown sugar to a mixing bowl.
Mix until well combined.
In a separate bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt.
Add the oats to the dry ingredients and mix well. mix until partially combined.
Add the milk, cinnamon, and mix until just combined.
Divide the batter evenly among the lined muffin cups. Bake at 180°C (350°F) for 18–22 minutes, or until golden and a toothpick inserted into the center comes out clean.
Let the muffins cool in the pan for a few minutes, then transfer them to a wire rack to cool completely. Serve and enjoy.
