Make the filling: Put the Idaho® potatoes in a saucepan and cover with cold water. Bring the pot to a boil, turn down the heat, and simmer until the potato chunks are tender and easily pierced with a fork, about 20 minutes. Drain the potatoes and put them back in the hot, empty saucepan to dry for a few minutes.
- While the potatoes are boiling, heat 4 tablespoons butter in a large skillet and add the onion. Cook until the onion is golden brown and very soft, about 15 minutes.
- Mash the potatoes with a potato masher or fork; it's okay if there are some lumps. Add the cooked onions, salt and pepper. Mix well, taste, and adjust seasoning if necessary. Set filling aside.
Make the pancakes: Whisk together the flour, egg, water and salt. The batter should have the consistency of heavy cream; if it's too thick, whisk in a little more water.
- Heat a small (7-inch) nonstick skillet over medium heat. Melt a little knob of butter in the pan and swirl it around so the bottom of the skillet is lightly coated with the melted butter. When the butter stops foaming, ladle in about 2 Tablespoons of the batter, swirling the pan around so the batter coats the bottom of the skillet evenly. Cook the pancake about 45 seconds, until the edges are starting to curl up. Do not flip the pancake - you're cooking it on one side only. Slide the pancake onto a plate, cutting board or cooling rack. Repeat with the remaining batter until all the pancakes are made. Wait to stack the pancakes until they are fully cooled or they will stick together.
Assemble the blintzes: Place one pancake on a cutting board with the cooked side up.
- Dollop about 2 Tablespoons of the potato filling in a rectangular shape in the middle of the pancake.
- Now form the blintz by folding in two sides of the pancake over the short edges of the rectangular filling, folding up one long edge, and rolling until the other edge is under the filling and the whole package looks like a little burrito. Continue with the rest of the pancakes and filling. Note that the uncooked side of the pancake is on the outside of the blintzes; this is as it should be, since you will be cooking the blintzes again once they are formed.
- To serve, heat a little more butter in the skillet and place the formed blintzes in the skillet. Fry until golden on both sides and the filling is heated through. Serve immediately with applesauce or sour cream (or both).
Time Saving Tip:
- cups Idaho® dehydrated potato flakes plus 2 cup boiling water may be substituted for the cooked and mashed potatoes in the filling.
- Mix together the potato flakes and the boiling water, then proceed with the recipe as directed. Blintzes can be formed up to 1 day ahead and refrigerated, stored in a single layer and covered tightly with plastic wrap.