I used frozen puff pastry as the bottom to the pie casserole. Filling: cooked spinach, feta cheese, sliced fresh onions, cutted ham, handfull of fresh herbs (I used lovage, thyme, oregano), 1 cooked and mashed potato (left over from my lunch), 1 egg, 1 dl milk, 1 dl cream, pinch of white pepper. Mix all filling ingredients, pour to pie casserole, spread on top with grated cheese. Bake +225 C (+437 F) 30 minutes.
Later I was thinking that some mushrooms (like chanterelles) would also go well in this pie.