1. All ingredients should be at room temperature - both the butter and the eggs. You should take them out of the fridge an hour before making the dough. This will prevent the batter from curdling.
2. Preheat the oven to around 180°C. If you prefer to bake with convection, please note that you need to set about  160 C less.
3. Prepare two baking sheets by lining them with parchment paper

make biscuit

1. Using a mixer with a paddle attachment or a handheld mixer, cream the butter with the powdered sugar and the aromatics (salt and vanilla sugar) until fluffy. This can take 5 minutes!
2. Gradually beat in the eggs. Only once the first egg has been completely absorbed by the butter and a homogeneous mass has formed you should add the second egg.
3. It is best to sift the flour through a fine sieve into the butter and fold it in with a spatula or a wooden spoon. Fill the mixture into a piping bag with a star nozzle.
4. Tip: Do not use disposable piping bags here. These break and rip quite easily and in most cases do not withstand the shortbread dough.
5. Now pipe the cookie batter onto the prepared sheet. Bake the cookies in the oven for about 8 minutes. Let them cool down and spread a small amount of jam in the middle of a cookie, then sandwich two cookie halves together, pressing them together gently.
6. Melt chopped chocolate and coconut oil over a hot water bath or in the microwave. The chocolate-fat mixture should not get too hot.
7. Dip one side of the cookies into the chocolate icing and leave to set on a piece of baking paper.