For the baked pineapple slices, mix flour with eggs. Add milk, rum, powdered sugar, vanilla sugar and salt.
Melt butter and stir in and let dough rest for about 15 minutes. Strain pineapple slices, pat dry and cut in half.
Dip pineapple in batter and fry in hot fat until floating. Drain on paper towels.
Arrange the baked pineapple slices on dessert plates and sprinkle with powdered sugar and cinnamon.