Oh, and did I tell you? I have a surplus of potatoes, too from last week's epic St. Patrick's Day brunch feast! Long Live the Irish! Recipe from the cookbook 'Clodagh's Kitchen Diaries' by Clodagh McKenna.
Cook the potatoes in a large saucepan of boiling salted water until tender. Drain, transfer to a bowl, and mash with a potato masher.
While the potatoes are still hot mix in the crème fraîche, egg yolk, mustard, and salt and pepper. Stir in the scallions, cheese and fresh herb/thyme.
Add 1 tablespoon of the flour to the mixture to help make the consistency suitable for rolling out. C G: At this point I would suggest transferring the mixture covered to the refrigerator and refrigerate at least 30 minutes. Chilling the potato mixture makes it easier to shape.
Sprinkle the remaining flour on your work surface. Roll the potato mixture out 2-inch thick using a rolling pin and cut it into circles using a 4-inch cookie or biscuit cutter.
Melt the butter in a frying pan and fry the potato cakes on both sides until golden brown.