A cake in a mug is a variant that gained popularity on many internet cooking forums and mailing lists. The technique uses a mug as its cooking vessel and can be done in a microwave oven. The recipe often takes fewer than five minutes to prepare. The cake rises by mixing vegetable oil (usually olive oil or sunflower oil) into a mixture of flour and other ingredients – as the oil in the mixture heats up, it creates air pockets in the mixture which allows the cake to quickly rise. This variant has become popularised in recent years by the presence of numerous videos on social media websites, each claiming to detail the fastest method to create the finished product.
A cake in a jar is another way of making cupcakes. The baker uses a glass jar instead of muffin tins or cupcake liners.