to make the dough for the buns, combine the water, milk, yeast, and 1 teaspoon of the sugar in a bowl and whisk together. let the mixture sit until the yeast is activated and foamy, about 10 minutes.
in the bowl of a stand mixer fitted with the dough hook, combine both flours, the salt, and the remaining 3/4 cups sugar. mix the dry ingredients together on low speed. keep the mixer running and slowly pour in the yeast mixture followed by the oil. increase the speed to medium and knead the dough until it is smooth and pulls away from the sides of the bowl, 5 to 7 minutes. if it does not start to pull away from the sides, add more flour, a tablespoon or two at a time. turn the dough out onto a clean work surface quickly so that you can oil your stand mixer bowl. transfer the dough back into the oiled bowl, flipping once to coat both sides, and cover the bowl loosely with plastic wrap or a clean kitchen towel. let the dough rise until doubled in size, 1 to 2 hours.
