word choice - "What I'm looking for is/are [plural noun]"

Which one of these is correct, and if both are correct in certain contexts, which is preferred?

• What I'm looking for is methods that help...


• What I'm looking for are the methods that help...

I know this may seem a duplicate of previous questions like Is it “5–6 weeks are a lot of time” or “5–6 weeks is a lot of time”?, but I think this is — not being about collective/mass nouns(?) — a somewhat different question.

(No, I'm not a native speaker of English.)