Recipe video above. Deceptively straight forward, it mainly takes patience! The 3 key things for a flawless, reflective mirror glaze are:1. Smooth frosting and level cake – because bumps and dents show up on shiny glazes. See my tutorial for How to Make Frosting Smooth on Cakes; 2. Ensure the glaze is completely smooth (just follow my recipe); and3. Ensure the glaze is at 30°C/86° so it spreads smoothly for a thin, flawless finish. Proper Mirror Glazes are no thicker than 3mm and are not made with condensed milk, for superior results (read in post for more info).Inactive cooling time includes time to cool Chocolate Ganache though directions to make and spread are in separate recipes (see Ganache recipe and Smooth Frosting post).