This is an adaptation of a Ukrainian recipe which uses sour cream. I found the original a bit rich so I tried it with yoghurt instead and it worked.
1 kg of potatoes
1 onion
250g yoghurt
Salt
A large bunch of fresh dill
Vegetable oil
Peel the potatoes, unless they're new potatoes in which case you can leave the skins on - I bet this recipe is absolutely brilliant with new potatoes. Slice the potatoes (about 1cm thick). Peel the onion and cut it in half then slice each piece. Mix the yoghurt with water until you have something the consistency of thin cream. You can prepare the dill while the potatoes are cooking. Wash it and stuff it into a cup then chop it finely with a pair of scissors.
Fry the onion until it is golden then add the potato slices and stir around a bit. Next add the yoghurt mix and some salt. Poke the potato slices around until they are lying flat and all more or less covered with liquid. Bring to the boil then cover with a lid. Simmer for about 25 minutes - until the potatoes are tender but not until they start to break up. When they are ready turn the heat off and sprinkle on the dill. It's ready to serve. Try serving it with veggie cutlets.