Preheat oven to 180 degrees. Line a 6 muffin pan and set aside.
Whisk together the dry ingredients in a bowl.
In another bowl, whisk the eggs, coconut oil, stevia and vanilla till well blended.
Fold in the dry ingredients into the wet ingredients till moist. Finally fold in the zucchini.
Divide the batter into the muffin holes. Press in 1/2 a square of chocolate into each muffin.
Bake for 30 minutes till skewer comes out clean. Cool completely before serving.