In a food processor pulse the pistachios, cardamom and flour till the nuts are a little chopped
Add powdered sugar and pulse more
Add the butter and pulse till you get breadcrumb texture
Add the egg yolk/cold milk. Keep pulsing till the dough comes together
Take the dough and roll it into a log.
Keep the log in the fridge for a couple of hours for the dough to harden
Pre heat the oven to 325 F
Slice the log into about 1/4 inch thick pieces and bake for 15-17 mins.
Let it cool completely.
Mix all the ingredients to make the glaze.
Take the cooled cookies, top with a small amount of glaze, decorate cookies with sliced pistachios, dried rose petals, saffron strands.