In a saucepan, cook the potatoes in water until tender. Drain well and mash.

In a frying pan, heat oil. Add onions and sauté until translucent. Add onions to mashed potatoes. Add the egg and salt and pepper. Mix to combine.

Place all the ingredients for the dough in an electric mixer fitted with a dough hook. Knead seven to eight minutes or until you have a smooth dough.

Preheat oven to 350 degrees Fahrenheit. Line two quarter-sheet pans or two 9×13-inch pan with Gefen Parchment Paper.

Divide dough in four. On a floured work surface or silicone mat, roll out to a 14×8-inch rectangle. Place one-fourth of the potato mixture down the center in the length of the rectangle. Fold one side over the filling, then fold the other side over. Place potato strip on the lined pan, seam side down. Repeat with remaining dough and filling, placing two strips on each pan.

Brush beaten egg over the strips. Using kitchen shears, snip a cut every inch along the length of each potato strip. Sprinkle with seeds and bake 45 minutes. Slice and serve hot or freeze whole. When ready to serve, allow it to come to room temperature and reheat 10 minutes in a 350-degree oven.