Soak raisins in rum for several hours. (This is important. Trust me. You want them well soaked!)
Melt butter in a pan over medium-high heat. (Look at it. Mmmm.)
Stir eggs with salt, then add flour, stir well, add milk, stir well. Add raisins, stir. (The mixture might appear a bit grainy, but trust me, it works.)
Pour batter into melted butter and cook until browned.
Flip, cook until other side is browned.
At this point, all the butter should be well cooked into the caramelized pancake. Scramble with a spatula.
Serve topped with powdered sugar and preserve. Feast like an emperor.