Beat eggs, sugar and oil until frothy. Then stir in the zucchini and carrots. Mix the nuts, flour and baking powder and fold in with the chopped chocolate.
Grease a muffin tin or line it with paper liners and fill in the batter evenly.
Bake in the oven at 180 degrees for about 20 minutes.
If you like, the muffins can be decorated with a little chocolate icing when they have cooled down.