Soak the raisins in the rum in a small bowl.
Melt 2 tbsp butter in a small pan. Separate the eggs. Pour the flour into a large bowl and stir in the milk with a whisk until smooth. Add the egg yolks, melted butter, 1 tbsp sugar, salt and raisins and stir until smooth.
Beat the egg whites with the remaining sugar until stiff then fold into the batter mixture.
Heat a pan and grease the edges with butter.
Add 1 tbsp butter to the pan. Add the dough and slowly brown on the underside for 3-4 minutes over a medium heat. Turn and cook the other side for 2-3 minutes until pale golden.
Slice the pancake onto the work surface and tear into pieces with 2 forks.
Pour some icing sugar into the pan and let it lightly caramelize.
Add the remaining butter.
Add the shredded pancake to the pan.
Cook, stirring, until coated in the caramelized sugar.
Dust with icing sugar and serve with cranberry compote.