For the potato rosti, mix the potato, shallots, flour, sea salt and freshly ground black pepper in a bowl. Add the oil to a heated pan. Using a teaspoon, spoon out heaped teaspoons of the mixture into the hot pan, turn to a low heat and flatten down, creating separate small discs of rosti. Fry until both sides are crisp, remove from the pan and remove excess oil on paper towels. Place to one side.