In a small bowl, whisk ground flaxseed meal with warm water and let sit for 5 minutes to create a flax egg.
Preheat oven to 350°F (175°C) and line baking sheets with parchment paper.
In a large mixing bowl, cream together the softened vegan butter, granulated sugar, and brown sugar until smooth.
Incorporate the flax egg, peppermint extract, and vanilla extract into the butter mixture.
In a separate medium bowl, sift together the flour, cocoa powder, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, stirring until a thick dough forms.
Fold in the vegan chocolate chips manually.
Scoop rounded tablespoons of dough onto the prepared baking sheets, spacing them 2 inches apart.
Bake for 10 minutes until the edges are set.
Remove from oven and immediately sprinkle the tops with crushed candy canes, pressing them lightly into the warm cookies.
Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.