Preheat oven to 350° Fahrenheit and line a 9x9-inch pan with parchment paper.
Melt the coconut oil in a large bowl in either the microwave or over the stove. Then, while the coconut oil is still hot, add in 1 cup of the chocolate chips and whisk until the chocolate has completely melted.
Add the eggs, coconut sugar, and vanilla extract to the melted chocolate mixture and whisk for 2-3 minutes until light and frothy.
Add in the oat flour, brewer’s yeast, cocoa powder, and ground flax seed then stir until the batter is completely smooth and combined. Fold in the additional ½ cup of chocolate chips.
Pour the brownie batter into your prepared baking pan and bake for 20-25 minutes or until the brownies are just set in the middle. Remove the brownies from the oven and let them cool completely before slicing.