I post this here because it's intended as an a multilingual comparison. Other languages welcome, but I can only state on those I speak (more or less).
In German, we'd usually say "einen Kuchen backen" (to bake a cake). Both "einen Kuchen machen" (to make a cake) or "einen Kuchen vorbereiten" (to prepare a cake) are possible, but I'd regard the first one as either solely referring to production or as poor German, and the latter as a little vague or ambiguous.
"Einen Kuchen präparieren", the most literal cognate, is yet different, I'd imagine someone hiding a tool (e.g. file) in it so that the recipient can escape from prison or something. Or possibly poison for other purposes, but anyway: adding something that's not a standard ingredient.
Before asking about Spanish: How is it in English? Do you make cakes or rather bake them or do you prefer to prepare them?