Japanese milk buns People come for our bugers; but, they stay for our buns. The bun is the most overlooked part of a burger; but, not at Copper Kings. These buns are soft, airy, and tender. They compliment flavor without overwhelming it. They can be smashed and return to there original shape. We bake our buns daily at Copper Kings along with most of our ingredients. A fresh baked bun makes for a superior burger.