Preheat oven to 350F.

Grease 12 muffin cups or line with paper muffin liners.

Beat brown sugar and coconut oil together in a bowl, add egg and beat until creamy.

Whisk flour, cinnamon, baking powder, baking soda, and salt together in a separate bowl.

Stir ½ the flour mixture into the coconut oil mixture.

Stir applesauce into coconut mixture, mix well.

Stir remaining ½ of the flour mixture into coconut oil mixture until just combined

Add oats and chocolate chips.

Pour muffin batter into prepared muffin cups.

Bake in the preheated oven until golden and the tops spring back when lightly pressed, about 25 minutes.