Preheat oven to 350°F (175°C) and line an 8x8-inch baking pan with parchment paper.
In a small bowl, whisk ground flaxseed meal with warm water and let sit for 5 minutes to create a flax egg.
In a large mixing bowl, sift together almond flour, cocoa powder, baking soda, and salt.
Whisk the flax egg, maple syrup, melted coconut oil, vanilla extract, and peppermint extract into the dry ingredients until a thick batter forms.
Fold in the dark chocolate chips.
Spread the batter evenly into the prepared baking pan, smoothing the top with a spatula.
Bake for 20 minutes.
Remove the pan from the oven and evenly distribute the vegan mini marshmallows over the top.
Return the pan to the oven and bake for an additional 5 minutes until the marshmallows are puffed and slightly golden.
Remove from the oven and immediately sprinkle with crushed candy canes.
Allow the brownies to cool completely in the pan for at least 30 minutes before slicing to ensure the fudgy texture sets.