a batter muffin that is puffy and almost hollow, it has risen so high. The ingredients are about the same as for Yorkshire pudding, and like Yorkshire pudding, the batter is poured into already-heated containers. The beating period is critical and cannot be skimped on, as the leavening agent is egg, which must be thoroughly aerated.
A popover is a light, hollow roll made from an egg batter similar to that used in making Yorkshire pudding. The name "popover" comes from the fact that the batter swells or "pops" over the top of the muffin tin while baking. They can also be baked in individual custard cups.