Potato and corned beef knishes

Whisk salt and baking powder into the flour; make a well and add the beaten egg, vinegar or lemon juice, plenty of oil and warm water; mix by hand to a very soft ball.

Knead on a floured surface 3 to 4 minutes until smooth, soft and elastic.

Rest the wrapped dough in the fridge for an hour or two.

Boil the peeled, quartered russets in salted water until just tender; drain well and mash.

Chop the corned beef and cabbage fine.

Cook the onion in melted butter over medium heat with a big pinch of salt, with the corned beef and cabbage, about 10 minutes until golden and the fat renders.

Mix into the potatoes with kosher salt, black pepper and cayenne; taste and cool to room temperature.

Press half the dough into a rectangle on a floured surface and roll to about an eighth of an inch thick.

Lay about three cups of cooled filling three inches from the edge; brush egg wash along the opposite edge.

Stretch the dough over the filling and roll up, leaving a couple of inches to stretch over the top; seam down, press the ends, trim.

Mark into eight equal portions with a bench scraper, then cut through with a floured side of the hand.

Stand each piece on a cut end and press into a puck, tucking into the center.

Brush the bottoms generously with oil, place on a lined baking sheet, brush all over with egg wash (optional).

Bake in the center of a 375 degree oven about 40 minutes until lightly golden; serve warm or at room temperature.