For the carnival doughnuts, make a yeast dough from the ingredients that come off the sides of the mixing bowl. Let rise for 1 hour, then form 20 balls, flatten and cover to rest again.
Bake in hot fat, floating, for about 1 minute on each side. Mix the jam with a little rum and fill the carnival doughnuts with it using a piping bag and sprinkle with powdered sugar.