Preheat your oven to 350 degrees and lightly butter a 6 inch Cast Iron skillet. Set aside.
In a small food processor, add the Hazelnut Meal, cocoa powder, baking soda, baking powder and salt and process until the meal breaks down and becomes lighter, and closer to the texture of flour. This only takes a minute or so. Set aside.
Using an electric hand mixer, beat the melted butter and coconut sugar until the sugar is just moistened. Add in the egg and vanilla extract and beat for 2 minutes, until the mixture turns lighter brown and the coconut sugar starts to break down.
Add the Hazelnut Meal mixture into the sugar mixture, along with the chopped chocolate. Stir until everything is evenly mixed.
Pour the batter into the prepared skillet and smooth down evenly with a spatula.
Bake until the top feels lightly crunchy, the edges begin to darken and a toothpick inserted in the middle of the brownie comes out clean, about 16-17 minutes.
Let cool for 5 minutes and DEVOUR.
*I also tried this with finely ground Almond Meal, as I know Hazelnut can be tricky to find. It tastes great and you can sub it directly and use 1 cup (3.5oz)