Coney Knishes

To create the dough, combine flour, kosher salt, and baking powder in a large bowl. Form a central depression by pushing the dry ingredients to one side. Add oil, warm water, beaten egg, and vinegar, mixing these ingredients together until the dough comes together in a cohesive mass. Remove the dough from the bowl and place it on a clean surface, where you can knead until it becomes smooth, elastic, and pliable. Wrap the dough in plastic wrap and refrigerate for at least 1 hour.

Concurrently, prepare the filling by submerging potatoes in a large pot filled with salted water. Bring the mixture to a boil, then reduce heat to medium-low and simmer until tender, approximately 20 minutes. Drain the potatoes and transfer them to a mixing bowl, where you can mash them until they reach your desired consistency. Set the mashed potatoes aside.

Chop corned beef and cabbage into fine, uniform pieces.

Melt butter in a large skillet over medium heat. Add onion, corned beef, cabbage, and kosher salt, stirring constantly until the onions are softened and golden brown, and the beef fat is rendered, approximately 10 minutes.

Combine the cooked beef mixture with the mashed potatoes in a bowl. Season with cayenne pepper, salt, and black pepper, mixing until the ingredients are well combined. Allow the filling to cool to room temperature.

Preheat your oven to 375 degrees F (190 degrees C). Line two baking sheets with silicone mats.

Divide the chilled dough in half; flatten one half into a rectangle on a floured surface. Roll out the dough into a larger rectangle, approximately 1/8-inch thick, using gentle stretching motions to achieve the desired thickness.

Place 3 cups of filling along one long edge, approximately 3 inches away from the edges. In a small bowl, whisk together egg and water to create an egg wash. Brush the egg wash over the opposite end and a little on the sides of the dough. Stretch the dough to cover the filling, then roll up toward the egg-washed side. Fold the last 3 or 4 inches on top, pressing in the filling as you go. Roll over so that the seam-side is facing downwards.

Trim off any excess dough from the ends if desired. Use a sharp object to mark, but not cut, the dough into 8 equal pieces. Using your hand, flour one side and press it against the counter to separate each piece. Position each piece with one cut-end facing downwards and the other facing upwards. Squish down the top and tuck everything into the center to form a round knish.

Repeat with the remaining dough and filling. Brush the bottoms of each knish with olive oil and place them on the prepared baking sheets. Brush any leftover egg wash on top.

Bake in the preheated oven until lightly golden brown, approximately 40 minutes. Let cool until just warm or room temperature.