。
She likes cake.
Literal
She [topic-は] cake [subject-が] like.
A textbook ~は~が好きだ template: は marks the topic (the person), が marks the subject of the stative predicate 好き ('liked'), and the copula だ closes the sentence. This is one of the first patterns introduced in any beginner course because it makes the は-vs-が pairing transparent: は frames who we're talking about, が tells you what the predicate applies to. 好き is grammatically a na-adjective even though it functions like 'like' as a verb in English — that's why what's liked is marked with が rather than を.