"bake a cake" is such a simple common phrase in English, something that just rolls off the tongue. In Spanish? What's the most common colloquial equivalent? Pls specify which country's Spanish you are referring to. Thank you :)
As native Spanish speaker From Colombia, I would say “preparar un pastel” ”Preparar una torta” “preparar un ponqué” is commonly used because the fact of prepare it and baking it is implicit in the term bake unless you have it set and after a while you go and only start the oven and bake it. But, you can say “hornear un pastel” as standard Spanish translation I have heard it on tv/movies translations but from where I come we usually say “preparar”. The term “preparar” would be more like “get ready the cake to be baked”.
I'd say that hacer, cocinar, preparar, hornear (this last one only if it's something that goes in the oven) all are understood across Spanish speaking regions. But which rolls of the tongue on the native population depends on the specific country/region.
So there's no one answer. In Chile is "preparar" too and in Spain it's "hacer" (even though as César mentions movie translations say "hornear")
Note that there are certainly some other "cocinar" synonyms that don't make sense in this context, like "asar un pastel" or "guisar un pastel"