Preheat oven to 350 F.

Grease baking pan.

Mix cooled mashed potatoes with condensed milk, lemon essence, egg yolks, and ground almonds well. No lumps of potatoes!

Beat egg whites until foamy, not too stiff but not runny, fold into potatoes mixture.

Pour mixture to baking pan, sprinkle some raisins on top, and bake until knife inserted comes out clean in the center (for at least 30 minutes)

Serve warm or room temperature. Serve with whipped cream, ice cream, chocolate sauce, caramel sauce, sprinkles of icing sugar is also good ^_^