Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a mixing bowl, combine almond flour, coconut flour, erythritol, baking powder, and salt. Mix thoroughly to ensure that all dry ingredients are spread equally.
Mix in the chilled, cubed butter. With a pastry cutter or your fingertips, chop the butter into the flour mixture until it resembles coarse crumbs.
In a separate bowl, whisk together the heavy cream, egg, and vanilla extract.
Pour the wet mixture into the dry mixture and stir until a dough forms.
Fold the chocolate chunks into the dough gently.
Turn the dough out onto a lightly almond-floured surface and shape it into a circle, about 1 inch thick.
Cut the dough into 8 equal wedges and place them on the prepared baking sheet.
Bake in the preheated oven for 18-22 minutes or until the scones are golden brown and a toothpick inserted into the center comes out clean.
Remove the scones from the oven and let them cool on a wire rack.