Recipes for Christmas pudding usually include dried fruit, flour, eggs, breadcrumbs and spices. Milk or alcohol is also present as the liquid to help bind the ingredients together.

Treacle pudding defies baking law. The name itself is a misnomer in the U.S.; it’s more of a cake than a pudding, and the cake isn’t even baked—it’s steamed in a basket. But in the U.K. and Ireland, ...