Preheat the oven to 170c/150c fan/gas 3. Put the softened butter into a bowl. Using a wooden spoon, gradually work in the rose essence and sugar until it is well mixed and forms a soft paste. Sift in the flours and, using a fork, bring together lightly to form a soft, crumbly dough. Then bring the mix to a soft, pliable, crack-free dough by kneading it as lightly as possible.
For the biscuits, place the dough between two sheets of lightly floured greaseproof paper. Using a rolling pin, roll out to a 5mm thickness. Remove the top paper and cut out the biscuits using a 6–7cm heart shaped cutter.
Place the biscuits on the baking sheets lined with parchment paper and bake until very lightly coloured; about 20 minutes.
Meanwhile dissolve the sugar with the lemon juice ready to brush on to the cooked biscuits.
Remove the biscuits when lightly golden and brush each with a little of the sugar syrup, sprinkle with the freeze-dried raspberries and pistachios. Bake for a further 5 minutes. Cool completely and pack into a pretty box, tin or bag and tie up with ribbon.