Preheat the oven to 350 degrees farenheit and line an 8 x 8 brownie pan with parchment paper, making sure there are flaps on all four sides. Spray lightly with cooking spray.

In a medium sized bowl, whisk together the dry ingredients.

In a seperate bowl, mix the ground flaxseed with the non-dairy milk. Let it sit for about 5 minutes.

Add 1/2 cup of the chocolate chips (reserving 1/4 cup for later) to the melted butter. Microwave in 30 second intervals until the chocolate is melted.

Add the melted butter and chocolate, sugars, and vanilla into the flax mixture. Mix well.

Fold the dry ingredients into the wet ingredients until fully incorporated. The batter will be thick.

Using a spatula, pour the brownie batter into the prepared pan. Spread the batter evenly and top with the remaining 1/4 cup of chocolate chips.

Bake the brownies for 35 minutes. While the brownies are baking, prepare the graham cracker crumbs by mixing the crumbs with the melted butter.

Remove the brownies from the oven and top evenly with the graham cracker crumbs and mini marshmallows. I like to do half the crumbs, the marshmallows, then top with the remaining crumbs. Gently press the crumbs and marshmallows down.

Return the brownies to the oven for an additional 5 minites. Optional: Broil for 1-2 minutes so the marshmallows get golden brown, but watch out - they burn fast!

Let the brownies cool completely before slicing. If they are not cool, they will be crumbly. Enjoy!