Mix mashed potatoes, egg yolks, sugar, juice of half a lemon and salt in a ladle with a thick bottom. Stir until smooth. Heat over medium heat with constant stirring until boiling. The mass will begin to thicken. The first big burst bubble is a sign that it's time to take it off the fire. It won't get any thicker, but it can easily get burned. We got custard, or cottage cheese, as it is called in England. Put the warm custard base in a glass. Gradually adding small pieces of butter, whisk with a blender until smooth. The longer you punch, the tastier - the emulsification process takes place, as in the preparation of homemade mayonnaise. If the cooled cream has a strong oily taste, it simply means that it is poorly mixed. Cover the cream with cling film and refrigerate for 30 minutes.
Interesting recipe but difficult to follow in the English language. What seems to be missing in the ingredient list is the amount of raisins to be used. Are the raisins optional or necessary to the recipe? Does one plump the raisins with water or the cognac? This is not quite clear in the instructions.
Thank you very much for the comment. You can use the raisins as you wish, I assume the taste will be even brighter.