Carefully place the puff pastry over the top of the skillet and fold over any long edges, then, working quickly, tuck and fold in the edges of the pastry so it sits just inside the rim of the skillet, to create a rough border.
Alternatively, cut the puff pastry in half, then layered it diagonally on top of each other so that it covers most of the pan (see pictures).
Brush the pastry with egg wash, garnich with nigella seeds (optional) and carefully score the top with a few slits to allow air to escape during baking.
Transfer the skillet to the preheated oven (middle rack) and bake for 20 to 25 minutes, until the pastry is golden and the filling is bubbling around the edges.
Serve and enjoy!
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