Add the potatoes and onions into a blender, blend until smooth.
Put the mixture through a sieve to drain about 3-4 tablespoons of excess juice.
Add the potato puree into a bowl and stir in flour, salt, pepper and stir.
In a large skillet, add enough just to cover the bottom the bottom of a skillet.
Once the oil is added, add the potato mixture to the skillet using a 1/4 measuring cup scoops for even sized pancakes.
Saute the pancakes until golden and crispy about 3-4 minutes per side. Remove to a paper lined tray. Repeat with remaining ingredients adding more oil if needed or use a second skillet.
Serve with sour cream.
Notes
Chef's tip: Though the blender is much quicker and easier to prepare the pancakes, grating the potatoes using a star side of a box grater will result in textured pancakes.