Corned beef hash is pure comfort food. It's easy to make, sometimes using leftovers, and fabulously tasty. In fact it reminds me of my childhood in north-east England, when we used to have a very similar dish that I thought was called fanackerty (I was only 6!) but I've later found is called Pan Haggerty. You can use corned beef from a can, or make your own corned beef.
How to make corned beef hash
If you are using leftover boiled or roast potatoes, just cut them into 1cm (half inch) cubes. If you are using a raw potato, peel and dice it, and pre-cook it by boiling in water with the stock cube for about 20 minutes. You only want enough liquid to cover the potato, and let it cook rapidly without a lid so the liquid evaporates - but stir it now and again to make sure the potato doesn't stick to the pan, and add a bit more water if required.
Meanwhile, peel and thinly slice the onion. Fry it gently in oil for about 10 minutes - you want it to be softened but not browned. When the potatoes are just tender, strain them and dry them on kitchen paper, then add them to the pan with the onions. Add more oil if required. Cook gently for another 10 minutes until the potatoes begin to get crispy on their edges, then cut the corned beef into 1cm dice and add it to the potatoes and onion. Cook for a few more minutes, and then your corned beef hash is done.
To serve corned beef hash
Serve on its own, or with a fried egg on top and baked beans.