A friend informed us recently that cupcakes in a jar are the hot thing right now. They've been seen on The Today Show and in O Magazine. Really, we said. We haven't even seen these things. What are they? Cupcakes in a jar, it turns out, are like the illicit love child of cake pops and those jarred cake mixes ubiquitous in holiday gift-giving. Have you tried one of these mashed confections of cake and frosting?