In the bowl of a stand mixer, combine the softened butter, lemon zest, and confectioners sugar and beat together on medium speed until creamy and combined.
Beat in the vanilla and rose water.
Reduce the mixer speed to low. Add the flour, salt, cardamom and pistachios and beat just until combined.
Turn the dough out onto some cling film. Press the dough together, forming a disc shape, about an inch in height. Wrap the dough with the cling film and place in the refrigerator to chill for 30 minutes.
Dust your work surface with flour. Roll out your cookie dough to about ¼ inch thick. Cut out the desired shapes and place on a parchment paper lined cookie sheets, leaving about 2 inches in between the cookies.
Place the cooking sheets into the refrigerator to chill for 30-45 minutes.
Preheat the oven to 350F while the cookies are chilling.
Once the cookies are properly chilled, bake for 15-20 minutes or until the edges of the cookies start to turn a light golden brown.
Let cool completely on the cookie sheets or on a cooling rack.
Place the white chocolate into a microwave safe bowl.
Melt the chocolate in 30 second increments in the microwave until the chocolate has melted.
Dip the cookies into the white chocolate.
Before the chocolate is set, sprinkle with chopped pistachios and top with edible rose petals. Let the chocolate dry, then serve.