Start by boiling the potatoes in salted water, covered, for about 30 minutes, or until tender. Drain the potatoes and transfer to a large bowl.
While the potatoes are boiling, chop the onions, green onions, and dill. Cook the onions, salt, and pepper in a skillet with the olive oil until soft, about 5 minutes.
Mix all ingredients together, while either crushing the potatoes slightly or slicing into small chunks. Season with more salt and pepper if needed.
Serve immediately, or put it in the fridge and serve chilled.
