Step 1
Preheat the oven to 190 degrees C (375 degrees F). Grease 24 muffin cups or line with paper liners.
Step 2
In a large bowl, sift together the flour, white sugar, baking powder, salt, and baking soda. Stir in the oats and chia seeds.
Step 3
In a separate bowl, mix the orange juice, applesauce, oil, and beaten eggs. Gently fold this mixture into the flour mixture until just combined. Carefully fold in the blueberries. Fill the prepared muffin cups about 3/4 full with the batter.
Step 4
In a small bowl, mix together the brown sugar and cinnamon. Sprinkle this mixture over the batter in the muffin cups.
Step 5
Bake in the preheated oven for 18 to 20 minutes, or until the tops spring back when lightly pressed.