A soft thin cake usually eaten with molasses.

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1792.  Naples biscuits, crackers, buns, and flannel-cakes.—‘Munchausen,’ p. 131. (N.E.D.)

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1847.  A very delicate species of food, which I tasted then for the first time, called flannel cakes.—Charles F. Briggs, ‘Tom Pepper,’ p. 111–2.

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