Popping candy — that novelty childhood sweet — is making a mature comeback on dessert menus across the country, bringing its celebratory tendencies to doughnuts, macarons, cookies and chocolates. The secret to its pop is pure science. It’s made by cooling down molten sugar in the presence of pressurized carbon dioxide, which traps the gas inside the sugar. Eating the candy releases the CO2 with a satisfying crackle. Fun fact: Popping candy won’t melt when it comes in contact with fats and oils, which makes it ideal for adding to such dreamy desserts as this luscious crème brûlée.