1) For the sugar cookie dough: whisk together the flour, salt, and bicarbonate of soda. In the bowl of your electric mixer (or with hand beaters), beat the butter and sugar until light and fluffy (about 3 to 4 minutes). Add the eggs and vanilla extract and beat until combined. Add the flour mixture and beat until you have a smooth dough. Divide the dough in half and wrap each half in plastic wrap. Refrigerate for about one hour or until firm enough to roll.
2) For the cookies: preheat the oven to 180 degrees C.
3) Open sugar cookie log and press into a rectangle on cutting board. Add pistachios and cherries, press into dough and then re-shape into a log. Slice into 1/2 cm thick rounds. Transfer cookies to a baking sheet.
4) Bake 7 to 11 minutes, until golden around the edges. Transfer to wire racks to cool completely.
5) While cookies are baking, melt white chocolate chips in a double boiler or bowl over simmering water.
6) When cookies are cool, dip bottom half of cookies into melted white chocolate and place on waxed or parchment paper to cool.