I just use bittersweet chocolate chips and chop them into pieces before I add them to the dough. I also buy shelled and salted pistachios because I’ve shelled 2/3 cup before and it took forever! If you want to go that route though, I respect you and your decision.
When rolling out the dough, the chocolate chunks will usually let you know when you’ve reached the right thickeness.
You don’t have to dip these shortbreads into chocolate if you don’t want to, but doing so is definitely a great choice!