。
Jane told us that cooking isn't difficult.
Literal
Cooking [topic-は] is-not-difficult [quotative-と] Jane [topic-は] us [to-に] said.
A double-は sentence: the first は marks 料理 as the topic inside the quoted clause, the second marks ジェーン as the sentence-level topic. The quotative と marks the boundary of reported speech. The quoted content uses plain form (むずかしくない) even in polite reported speech — Japanese doesn't backshift tense the way English indirect speech does.