It refers to black praiseworthy bread, which is usually made by adding ingredients such as rye flour or caramel sauce during the production process. In addition, after mixing cocoa powder with flour, it can make it look black, then add butter crust and sprinkle with crisp chips, and smell a fragrance as soon as it is baked.
Taking black truffle cuttlefish salt as an example, cuttlefish juice is added to the dough, and the same black truffle is wrapped in the dough. When baking, the butter melts, and the rich aroma of full butter and black truffles is a good "blackening" presentation.