Chinese Doughnuts

Stir the water, sugar, baking powder, baking soda, salt and alum powder together in a large bowl. Let stand until small bubbles form.

Stir in the flour and mix until the dough is stiff and smooth. Turn the dough out onto a lightly floured work surface. Knead, adding more flour as necessary to prevent sticking, until the dough is smooth and elastic. Cover the dough with a damp cloth and let stand, until slightly puffy and soft.

Knead the dough again, recover, and let stand.

Knead the dough briefly to remove any air bubbles. Rub the 1 tablespoon oil over the surface of the dough, then place the dough in a resealable plastic bag. Seal the bag, then press the dough inside the bag into a rectangle. Let the dough rise in a warm location of the kitchen until it puffs slightly.

Place the dough on a lightly floured surface. Flatten and stretch the dough to make a 12- by 8-inch rectangle about 1/4-inch thick. Cut the dough crosswise into 12 strips, each about 2/3- to 1-inch wide, then cut the strips in half crosswise.

Form the doughnuts: stack two strips of dough, one atop the other, then press a thin chopstick lengthwise along the center of the top piece of dough to seal the two pieces of dough together.

Pour enough oil into a wok to fill 3 inches. Heat to 350 degrees. Hold the ends of one of the doughnuts, stretch it out to about 6 inches, then carefully slip it into the hot oil. The doughnut will shrink in length then puff. Fry the doughnuts, a few at a time, turning continuously until golden brown. Remove the doughnuts with a wire skimmer or slotted spoon and drain on paper towels. Fry the remaining doughnuts. Serve with jook or sprinkled with powdered sugar.