Combine all of the dough ingredients and mix and knead them — by hand, mixer, or bread machine — to make a soft dough., Place the dough in a lightly greased bowl, cover, and let rise in a warm place for 1 hour, or until it's almost doubled in bulk., Turn the dough onto a lightly greased surface, gently deflate it, and divide it into 6 pieces. Roll each piece into a ball., Place the balls into the greased cups of a hamburger bun pan, flattening gently. Or place them on a lightly greased or parchment-lined baking sheet, leaving about 2" to 3" between them; flatten gently., Cover and let rise until the buns have doubled in size, 60 to 90 minutes. Towards the end of the rising time, preheat the oven to 350°F., Bake the buns for 15 to 20 minutes, or until they're light golden brown., Remove them from the oven, and brush them with melted butter, if desired., Transfer the buns to a rack to cool. Store buns, well-wrapped, at room temperature for several days; freeze for longer storage.