The night before, make the beet purée by adding 1/8 cup boiling water to 1/16 cup Dr. Cowan’s Garden Powder; whisk and refrigerate overnight, covered.
Preheat the oven to 350 degrees.
In a small saucepan on lowest heat, or over a double boiler set over boiling water, melt the chocolate bar with the coconut oil. Stir till completely melted and blended.
Add the maple syrup and stir till combined. Set aside.
Grease an 8-by-8-inch square pan with coconut oil and coconut flour.
Whisk together the eggs and vanilla extract in a small bowl. Add the chocolate mixture and whisk until incorporated.
In a medium blow, whisk together the 2 tablespoons of coconut flour and the quinoa (or almond) flour, cocoa powder, baking soda, sea salt, cinnamon and cardamom. Add the chocolate-egg mixture and stir until fully combined.
Stir in the beet purée, then add the chocolate chips and stir gently to combine.
Pour batter into prepared pan and bake for about 25 minutes, until a thin knife inserted into the center comes out clean. Allow to cool in the pan for at least 30 minutes before cutting.