Blooming cocoa powder in a hot liquid can intensify the chocolate flavor in your cake, unlocking the rich aromas and deep flavors. This technique eliminates clumps, so you can skip sifting the cocoa powder. Most chocolate cake recipes require a liquid, like water or coffee, and some call for milk, melted butter, hot oil, or Guinness or red wine. The technique is similar to brewing coffee with hot water or blooming spices in hot oil. It's also beneficial for recipes that don't require any liquid, or for not enough liquid to dissolve the cocoa. However, it is not recommended substituting cocoa powder for melted chocolate or butter, as it could alter the cake's texture.