In a mixing bowl, combine warm water, sugar, and yeast. Let it sit for 5 minutes until frothy.

Add flour, salt, and vegetable oil to the yeast mixture. Mix until a dough forms.

Knead the dough for about 10 minutes until smooth. Let it rise in a warm place for 1 hour.

After the dough has risen, punch it down and roll it out to about 1/2 inch thickness.

Cut out circles and place a spoonful of red bean paste in the center of each. Fold and seal the edges.

Heat oil in a frying pan over medium heat. Fry the donuts until golden brown on both sides.

Remove and drain on paper towels. Serve warm.