In a mixing bowl add the soft butter and powdered sugar. Cream them together using a whisk or blender until they are well combined.
Next, add in the yogurt and mix everything together. Next add in the Wheat Flour, Salt, and Baking soda.
Mix everything together and then add in the grated chocolate. Mix well it may resemble crumbs. If it is too dry add in a tsp of milk and bring everything together. Ultimately it should resemble cookie dough.
Line a baking tray with parchment paper. Add-in the prepared chocolate cookie dough and flatten it with any vessel.
Preheat the oven at 180 Deg C for about 10 ins and then bake at 180 Deg C for about 15 mins. Remove from the baking tray and then cut them into squares once its cooled completely and serve.
Notes
The baking time may vary so check after 20 mins.
You can also use choco chips instead of the grated chocolate.
Cut them into cubes,cool completely, and refrigerate till use. It stays good for about 5 days.