Make your kagecreme by following the recipe here. This ensures that it has time to cool down before you make the cremestang. To make the dough: heat up the milk, either in the microwave or in a saucepan, until it is “fingervarm” (finger warm), meaning it should feel warm to the touch but not hot. You don’t want to kill the yeast! Add the yeast and stir to dissolve. Let it rest 5-10 minutes until it begins to froth and bubble a little bit. (If your yeast doesn’t do anything, it may be expired. Check the expiration date on the package and start over with new yeast!)
Combine the egg, egg yolk, sugar, vanilla extract, cardamom, and salt in a large bowl. Mix well.
Add the milk and yeast mixture to the egg mixture and whisk to combine.
Slowly add the flour, stirring with a wooden spoon. Once the dough starts to come together, you can start kneading.
Add the softened butter and knead until smooth and elastic, probably around 5-10 minutes. Add a bit of flour if the dough sticks to your hands or the surface. If you prefer not to get your hands messy and covered in butter, feel free to use a stand mixer for this step. The texture of your dough before its first rise should be soft and smooth, not sticky and not too dry.
Cover and let your dough rise for about an hour, or until doubled in size.
Once your dough has risen, divide the dough in half and roll out into a rectangle.
Fold over the two long edges to create a channel down the center.
Press down the edges of the dough to seal it so it doesn't unfold. Repeat with the other half of the dough.
Add the cooled pastry cream to the channel down the center.
Let the loaves rise for another 45 minutes until about doubled in height. Preheat your oven to 375 degrees F (190 C).
Once it has risen, brush the dough with a beaten egg and top with sliced almonds and some pearl sugar.
Bake for 15-20 minutes until golden brown and baked all the way through. Enjoy!