Combine all of the dough ingredients in a large bowl, and mix and knead — using your hands, a stand mixer, or a bread machine set on the dough cycle — to make a soft, smooth dough.
Place the dough in a lightly greased container — an 8-cup measure works well here — and allow the dough to rise for 60 to 90 minutes, until it's just about doubled in bulk.
Gently deflate the dough, and transfer it to a lightly greased work surface.
Divide the dough into 16 equal pieces, by dividing in half, then in halves again, etc. Round each piece into a smooth ball.
Lightly grease two 8" round cake pans. Space 8 buns in each pan. Can you use 9" round cake pans, or a 9" x 13" pan? Sure; the buns just won't nestle together as closely, so their sides will be a bit more baked.
Cover the pans, and allow the buns to rise till they're crowded against one another and quite puffy, about 60 to 90 minutes. Towards the end of the rising time, preheat the oven to 350°F.
Uncover the buns, and bake them for 22 to 24 minutes, until they're golden brown on top and the edges of the center bun spring back lightly when you touch it. An instant-read thermometer inserted into the middle of the center bun should register at least 190°F.
Remove the buns from the oven, and brush with the melted butter. After a couple of minutes, turn them out of the pan onto a cooling rack.
Serve warm. Store leftovers well-wrapped, at room temperature.