Coarsely grate the potatoes and shallot into a tea towel. Squeeze to remove excess liquid, then place in a large bowl. Add the eggs, flour, seasoning and mix well.
Pour 3cm of oil into a high sided pan.
Once hot, carefully spoon in large tablespoons of the mixture. Fry in batches to avoid overcrowding. Cook on each side for around 3 minutes until a deep golden brown. Remove to a plate lined with kitchen paper.
Serve with an extra sprinkling of sea salt and the chives, with bowls of the sour cream and apple sauce on the side.