In a glass measuring cup with a spout, combine the ¾ cup warm water, yeast, and pinch of sugar. Stir to combine. Let sit for 10 minutes or
so, until the mixture is frothy. Stir in 2 tablespoons oil.

In a large mixing bowl or the bowl of a stand mixer, combine the flour, baking powder, salt, and the remaining 2 tablespoons of sugar.

With the mixer running (or while stirring by hand), add the yeast mixture in a slow, steady stream, mixing until the dough comes together
in a ragged ball. The dough should hold together and be a bit sticky to the touch. If needed, add an additional 1 to 4 teaspoons of warm water while mixing. If using a stand mixer, knead for about 3 minutes.

Turn the dough out onto a board and knead by hand for an additional 3 to 6 minutes (longer if you didn’t knead it in the stand mixer) to
form a nice, smooth ball.

Oil a large bowl and place the dough in it, turning once to coat with oil. Cover with plastic wrap, pressing the wrap directly onto the dough. Set in a warm place, such as on your kitchen countertop, and let rise until doubled in size, 1 to 2 hours.

Turn the dough out onto a lightly floured board and split it into to 2 roughly equal-sized pieces. Roll each piece into a log and, using a knife, cut each log into 8 roughly equal-sized pieces. Roll each piece into a ball and then, using a rolling pin, roll each into an oval about 3 inches wide
by 4 ½ inches long and ¼-inch thick. Fold each oval in half to make a semi-circle. Set each bun on a small square of parchment paper.

To cook the buns, place them in a steamer basket (Don’t crowd the basket as the buns will puff up as they cook and will stick together if they are too close. You may need to cook them in several batches. If you have stacking bamboo baskets, you can stack 3 baskets at a time.) Set the steamer over boiling water and cook for about 10 minutes.

Serve hot, with fillings, and let diners fill their own buns.