Preheat oven to 350°F.
In a large bowl combine the oat flour, cocoa powder, Magical Reishi Powder, baking soda, and salt and set aside.
Combine melted butter and dates in a food processor or stand mixer until it forms a thick and pasty mixture.
Scrape the mixture from the bowl into another bowl, then add in your egg and vanilla. Stir until well combined.
Add the dry ingredients to the wet ingredients and stir until thoroughly combined. The batter will be very thick and shiny.
Spread the batter into a greased 8x8 pan lined with parchment paper (this will make it much esier to remove once baked).
Bake at 350°F for 12-15 minutes.
Once cooled, cut into squares and top with powdered sugar. Enjoy!