1. Preheat the oven to 180°C (350°F). Line a muffin tin* with (tulip) paper liners* and set aside. Grate the zucchini. Chop the chocolate. Set everything aside.

2. Mix flour, cocoa powder, baking powder, baking soda, and salt in a bowl. In a second large bowl mix xylitol (or sugar), sunflower oil, milk (or oat milk), egg, and vanilla extract until well combined. Add the dry ingredients to the bowl and mix until just combined. Add the grated zucchini and grated chocolate and fold in. Divide the batter between the paper liners and press a piece of chocolate into each portion of dough. Bake the muffins for about 20-22 minutes or until a toothpick inserted into the side of a muffin (not the chocolate center) comes out clean. Take out of the oven, remove the muffins from the muffin tin and let cool down completely on a wire rack.