1. You have to start in the evening with the preparations so you can bake the next day. The dough needs time to rest and rise overnight. I recommend reading the whole recipe first ;)

2. Start with the butter package you need to laminate the dough. Cut the butter into 0.4 inches thick strips and place them next to each other on a large piece of baking parchment. Fold the paper over the butter and create a square package with a size of 7×7 inches. If you have sharp edges you can now simply roll/press the butter into shape with a rolling pin. You need a butter package/layer to have that exact dimensions. Place in the fridge overnight.

3. For the dough add spelt flour, sugar, and salt to the bowl of a food processor (with dough hook) and mix to combine. Add milk, butter, egg, and egg yolks. Crumble the fresh yeast and add to the bowl as well. Knead for about 8-9 minutes until you get a nice and smooth dough. Take the dough out of the bowl and knead again briefly with your hands on a lightly floured surface, then shape into a ball. Use a sharp knife and cut a cross into the dough (about 2 inches deep). Place in a large bowl and cover (e.g. with cling film). Place in the fridge overnight (about 10 hours).

4. For the custard filling mix cornstarch, sugar, salt, and vanilla extract with a few tablespoons of the milk until well combined. Heat the remaining milk together with the butter in a small saucepan. As soon as the milk starts to boil, stir in the cornstarch mixture and allow the custard to thicken. Let it bubble for a moment while stirring constantly, then remove from the heat and leave to cool for a minute or so. Stir in the egg yolk, then immediately place a piece of plastic wrap directly on top of the custard (to prevent skin from forming) and let cool down completely.

5. For the marzipan filling, mix the marzipan paste with butter, sugar and vanilla sugar until smooth. Cover and leave it on the counter at room temperature until needed. The butter, dough, pudding, and marzipan filling can all be prepared in advance.

6. The next morning, take the dough out of the fridge and roll out into a rectangle (14×7 inches) on a lightly floured surface. Place the butter (without the paper) in the center of the rectangle. The butter should be flush with the long edges of the dough on the left and right. Fold the dough over the butter to enclose it completely. Press the edges together. Turn the package in a 90° angle. Use the rolling pin to carefully press the butter and dough together and then roll out to create another long rectangle. If the shorter sides are a bit wonky due to the shaping of the dough, trim them a little to get straight edges.

7. Fold the short sides of this long rectangle towards the center so they meet exactly in the middle. Fold once more together as if you were closing a book – you should now have a total of four layers of dough stacked on top of each other. This is the first »tour« to get a nice lamination. Wrap the dough loosely in plastic wrap and place in the fridge for about 30-45 minutes.

8. For the second »tour«, roll out the dough once again on a lightly floured surface. Make sure the side of the package that shows all four layers is facing you, then roll out working away from you. You want a long rectangle again, bit shorter than the first time. This time you have to fold the dough only once towards the center and the other side on top of that – this will create three layers. Wrap in plastic wrap once again and place in the fridge for another 30-45 minutes.

9. Roll out the chilled dough on a lightly floured surface into a rectangle with a size of about 18×14 inches. Cut out squares with a size of about 4.3×4.3 inches. The rectangle is slightly larger than you need so you can smooth out any unsightly edges, if necessary. Add a small portion of marzipan onto each dough square and fold all four corners towards the center to enclose the filling completely. Place the Danish pastries on two baking sheets lined with baking paper (6 pieces per baking sheet) and cover loosely with plastic wrap. The dough has to be able to rise undisturbed. Let the pieces rise in a warm place for about 1 1/2-2 hours – the volume of the dough should have visibly increased. The rising times depend greatly on the room temperature.

10. Preheat the oven to 375°F (190°C). Mix the pudding once again to get rid of any lumps (e.g. with an immersion blender). Whisk egg yolk and some heavy cream to create an egg wash and brush the risen Danishes with it – be gentle. Use a spoon (or your fingers) and carefully press an indention into the centers of the Danish pastries. Add about 1 tablespoon of custard and a small amount of jam into each indention. Place the first tray of Danishes in the center of the oven and bake for about 20-23 minutes. The pastries should have risen nicely with a nice golden brown color. Bake the second baking sheet the same way. Transfer the Danishes to a wire rack and let cool down completely. Decorate with some sugar glaze, if desired.