For the macadamia slices, preheat the oven to 170º C hot air.
For the dough mix sugar, butter and vanilla sugar until very fluffy, add the egg yolk and knead with the flour.
On a smaller baking sheet lined with baking paper, spread the dough mixture about 1 cm high and smooth it out. Bake for about 15 minutes. Let cool on the baking sheet.
For the cream, heat all ingredients except the macadamia nuts, stirring constantly, until thickened. Then mix in the macadamia nuts.
Now spread the nut mixture on the already baked pastry. Bake at 160 ºC for about 10 minutes.
In the meantime, melt the chocolate. Spread the chocolate over the baked mixture and smooth it down.
Finally, sprinkle with chopped macadamia nuts. Let cool and then cut into slices. Store macadamia slices in a cookie jar until ready to serve.