ケーキを作るときには、卵、バター、砂糖を使わなければいけない。

cake

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to make; to produce; to manufacture; to build; to construct; to prepare (food); to brew (alcohol); to raise; to grow; to cultivate; to train; to till; to draw up (a document); to make out; to prepare; to write; to create (an artistic work, etc.); to compose; to coin (a phrase); to organize; to organise; to establish; to found; to have (a child); to make up (one's face, etc.); to fabricate (an excuse, etc.); to form (a line, etc.); to set (a record); to commit (a sin, etc.)

by the way; incidentally; sometimes; occasionally

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

eggs; egg; spawn; roe; hen egg; (an expert) in the making; beginning; origin; infancy

butter

sugar

to use (a thing, method, etc.); to make use of; to put to use; to use (a person, animal, puppet, etc.); to employ; to handle; to manage; to manipulate; to use (time, money, etc.); to spend; to consume; to use (language); to speak