Cover the oven pan with half of the puff pastry, pulling up one edge. Scatter the breadcrumbs on top and distribute the meat on top. Dice the onions and fry them in a little oil. Then distribute on the meat. Season with parsley and oregano. Then put the ham slices on top and spread the sliced tomatoes and cucumbers on top.
Place the remaining puff pastry on top as a lid. Brush with egg yolk and prick several times with a fork. Bake on the middle shelf at 225 ° C for 30 minutes.