Sift whole wheat flour and keep aside. In another bowl, take yogurt and sugar. Whisk till sugar dissolves.
Add baking powder, baking soda and mix. After a few minutes, it will turn frothy.
Add oil and mix. Slowly add the sifted flour little by little and make a lump free batter.Add chocolate chips, cocoa powder and mix to combine but do not over mix.
Line a muffin tin with paper liners and pour the batter to 1/2 the level.Stick in a marshmallow into each liner and top with with a little bit of batter.Bake in a pre heated oven at 180 degrees for 15 minutes or till a skewer inserted in the center comes out clean. Cool on a wire rack .
Delicious cupcakes are ready to be savored.