In a bowl place the egg yolks and vinegar over a medium saucepan of simmering water, whisking yolks and vinegar constantly. When reached a ribbon pattern consistency while continuing to whisk, remove from the heat. Whisk in melted butter slowly and season with salt and lemon juice.;
In a mixing bowl, combine potato puree, flour, cream, eggs, and salt and mix well. Pass through a fine sieve to ensure there are no lumps. Heat 4 roesti pans with a teaspoon of oil in each. Spoon the mixture evenly into each pan once hot. Cook until edges become golden brown. Take the pans off the heat and place into a hot oven. Bake for about 8 to10 minutes and then finish under the salamander to get an even golden color.
Serve with Hollandaise sauce.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.