Finely chop the garlic and stew into the butter, add spinach and let shrink, let cool. Roll the puff pastry open and spread the mustard in the middle in more or less a rectangle, place the raw salmon fillets next to each other in a long rectangle and season with salt and pepper. Squeeze the spinach a little and divide on top of the salmon and the cheese on top, hold an elcaser to sprinkle on top.
Now cut the 2 sides of the dough into 2 cm strips and now cross them alternately and step -by -step, make sure you see more or less no filling. Brush with beaten yolk and dash of milk, sprinkle with the cheese and sesame seeds.
Bake for 30 minutes in a preheated oven at 185 ° or until it looks nicely golden brown. Let cool and cut slices with a bread knife.