Chop the green onions and sauté them in a pan with a little oil. It should turn glassy in the process.
In the meantime, cut the ham and Gouda cheese into small pieces and place in a bowl. Drain the mushrooms and add. After the onion pieces have cooled down a bit, add them too.
Preheat the oven to 175 degrees.
Grease a springform pan well and then line it with the puff pastry, cut off the overlapping dough and place it where there is no dough on the edge of the springform pan. Finally, pour the well-mixed ham and cheese mixture onto the puff pastry. Put in the oven for 30 minutes.
Mix the egg yolks well with the cream. After the 30 minute baking time, distribute evenly over the cake. Bake for another 10 minutes.