Mix protein powder and yoghurt in a bowl until crumbly.
Add water gradually if needed and continue mixing until it forms a dough.
If it’s too dry, add a little more water, if too wet, add a bit more protein powder.
Knead into one ball, then place on baking paper and flatten into a rectangle.
Add chocolate chips if using, press them in, then cut into 4 equal bars.
Store in the fridge or freeze for later.
