Serves for 8:
Preheat the oven to 180ºC
Grease the rectangular baking pan with butter.
In a bowl, beat the butter and slowly add the sugar, beating the mix until you achieve a pale colour and a consistency of froth.
Add the whole eggs and the egg yolks, one by one, beating, and then add the flour and a pinch of salt.
Add the rum, all the raisins and the orange and citron candied peel.
Put the mix into the baking pan and bake the plum cake for 30 minutes or until it is cooked.
Remove from the oven and let cool before unmolding.