There is a great variety of fillings, my favourite is tuna fish, or chorizo, but there are from fish to sea food to vegetables.
You can also make “empanadillas” following the same recipe, which are more the size of small Cornish pasties but obviously it is more laborious. Another version for the small ones is to fry them instead of cook them in the oven.
Put a bit of oil to a frying pan, when it is hot add the chopped onion and cook until they get golden colour, add the eggs, the tuna fish , olives and peppers, cook for a couple of minutes and add the tomato sauce mix all and reserve.
Add the boiling water and wine to the oil, add salt and stir a bit, add the flour a bit at a time until it is not sticky but it is not too hard either.
Split the pastry in two. Work it with a rolling pin, cover a mould with it and add the filling ingredients, cover with the rest of the pastry and fold the sides over. Whisk an egg white and a little bit of water and brush the empanada with it.
Cook in the oven at 200C around 45 minutes.