Type of Rusk Whose German Name Means Twice Baked

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Question is: Type of Rusk Whose German Name Means Twice Baked

and the answer is: ZWIEBACK

Word Meaning:

ZWIEBACK — A form of rusk, usually sweetened bread enriched with eggs that is baked and then sliced and toasted until dry and crisp; considered easy to digest and therefore given to the ill and used as a teething food for toddlers.

Definitions from Wiktionary.