Whisk butter so that it is fluffy. Beat in all the other ingredients and put aside for about 10 minutes. Preheat oven to 180°C. With a help of a tablespoon add some pastry on a baking sheet and flatten. Bake for 5 minutes.
Peel and slice rhubarb and start to warm it with the sugar. After sugar is molten, but not caramelised add rose water and let it cook for a minute. Puree and add with vanilla sugar beaten heavy cream. Pour it to the ice cream machine and let it do the rest. Before it is ready stir in the honeybee pollen.