Potatoes are one of the most delicious fillings for dumplings or pies - but it is very important to cook them correctly. My grandmother used to make this filling, I learned it from her and I don't make it any other way, it's always successful. I will upload another potato filling, this time inspired by my grandmother from Ukraine, but a bit later :)
Wash the potatoes well, place in a pot with enough water to cover them completely and boil. I cook them for about 40-45 minutes, until the knife enters a potato easily.
In the meantime, peel and wash the onion, then finely chop and fry in oil until lightly browned.
When potatoes are done, drain the hot water and pour cold water in the pot. Leave for 5 minutes, then start peeling them. It's important to peel them now and not after they have cooled completely.
As you peel the potatoes, crush them with a spoon or a potato masher. It's also very important to do this while they are still warm, they have a different texture - take my word for this, I tested :)
After crushing the potaoes, let cool a bit.
Now add the grated cheese, the fried onion together with the oil, pepper. Mix well, taste, and, if necessary, add a little salt - it depends on how salty the cheese is.
That's about the whole process - you can prepare this filling in advance and keep it in the fridge for 1-2 days until you use it. It goes very well with pies, dumplings, puff pastry pies.
Enjoy!