Put yeast and 1 tablespoon of the sugar into a bowl. Pour in warm water, stir, and let mixture stand 5 minutes to dissolve. It should foam and bubble. If it does not, discard and use a fresh package of yeast. Put flour and remaining sugar in a food processor fitted with the metal blade. Turn machine on for 2 seconds to mix ingredients. Combine yeast mixture with warm milk and, while the machine is running, pour milk down the feed tube in a steady stream. Process until dough forms a rough ball. If the ball is sticky, add flour, 1 teaspoon at a time, and process a few seconds longer until dough pulls away from sides of bowl. Remove dough to a lightly floured board. Knead, dusting with flour until dough is smooth and elastic, about 2 minutes. Form dough into a ball and put it into a large, lightly oiled. mixing bowl. Cover and set in a warm spot. Let rise until it doubles in size, about 1 hour. Punch down dough and turn out on a lightly floured surface. Flatten, then put the baking powder in the center. Fold over edges and knead until baking powder is thoroughly incorporated. Invert, mixing bowl over the dough; let rest 10 minutes. Divide dough in half. Cover one half, and roll the other half into 12-inch-long roll; cut into 12 pieces. Remove 1 piece and cover rest. Roll the piece into a flat 3 1/2 inch circle. Lightly brush one with oil; fold over to form a half moon. With the back of a knife score the half-moons crosswise at 1/4-inch intervals. Then with a chopstick, make an indentation in the middle of the rounded edge while the thumb and forefinger pinch the middle of straight edge to form a notch and form a leaf. Set on a 3-inch square of parchment paper and place in a steaming basket. (You will need 2 baskets, or youll need to steam 2 separate batches.) Repeat with remaining dough; leave space between buns in the basket. Let rise for 30 minutes, or until buns almost double in size, then steam over boiling water for 15 minutes. When done, let cool for a minute before serving. Makes 24 buns. PER BUN: 90 calories, 2 g protein, 18 g carbohydrate, 1 g fat, (0 g saturated), 1 mg cholesterol, 33 mg sodium, 0 g fiber. Joyce Jue writing in the San Francisco Chronicle, 11/25/91.