Mix the flour, baking powder and baking soda well in a bowl.
In a second bowl, beat the egg and sugar until creamy, then fold in the oil well. Add yogurt. Then sift the flour mixture over it and stir in well. Finally fold in the chocolate chips.
Bake at 175 ° C for about 15-20 minutes.
Grate the chocolate and sprinkle it on the hot muffins immediately after baking so that it runs a little.