For the elderflower liqueur, remove the thick stems from the elderflowers and place them in a large glass with the sliced lemon and rock candy.
Then pour the grain over it. Put the jar in the sun for 6 months and shake it again and again. Then boil a lauter sugar from the water and the sugar and let it cool down.
Strain the elderberry liqueur and mix with the lauter sugar, mix well and pour into clean bottles.