Preheat oven to 350 degrees F. Line a large baking sheet with parchment paper and set aside.
In a large mixing bowl, add oats, flour, flaxseed, cinnamon, baking soda, and chocolate chips. Stir to combine.
In a medium mixing bowl, add peanut butter, applesauce, honey, brown sugar, and egg. Stir to combine.
Add the wet ingredients to the dry ingredients and stir well to incorporate all ingredients.
Scoop a heaping tablespoon of cookie dough and place it onto the prepared baking sheet. Using clean hands or the bottom of a cup or bowl, smash the cookie so it flattens. The cookies do not spread out much during the baking process, so this step helps get the cookie shape. Add a few more chocolate chips on top for presentation.
Bake for 9-11 minutes or until cookies are a golden brown and have firmed up a bit.
Allow cookies to cool on baking sheet for 2 minutes before transferring them to a wire rack to cool. Store in an airtight container for 3-4 days.
This makes a great hearty cookie for breakfast or snacks on-the-go, a guilt-free dessert option, or a high protein after school snack. Chocolate chips may be substitutes for raisins or similar dried fruit, or even nuts.