Dissolve yeast in warm milk with a bit of sugar and 1/2 cup flour. Let it stand until frothy. To the yeast mixture, add the egg, vanilla, remaining sugar, softened butter, salt, cardamom, mace, cinnamon, and lemon zest.
Knead the soaked fruits and almonds into the dough. If the dough becomes too sticky from the moisture of the soaked fruit, add 1-2 tablespoons of flour and knead again (I do this in a stand mixer).
Preheat the oven to 350°F (180°C). Bake the Stollen for 35-40 minutes. Melt 2 tablespoons of butter. After baking, while the Stollen is still hot, prick it all over with a toothpick (about 50 times) and brush generously with the melted butter.