It is historically recognized that the provenance of sen-bei, 煎餅, is China, specifically introduced during the Heian era. Those early continental wafers were composed of wheat flour; however, owing to the Japanese preference for kome, 米, rice,  became the primary ingredient for these sweets.   Sen-bei, 煎餅, toasted-mochi named ‘Matsu no Fū’, 松の風, Pine’s Wind, by Sue-tomi, 末富, Posterity-wealth, Kyōto. Showing both sides of the wafers. Note the outline of a square in the middle of the wafer, which is the silhouette of the small block of mochi flattened to create the senbei. Left: fuchi-daka, 縁高, edge-high, black-lacquered octagonal box with dai-fuku, 大福, great-fortune, bean-jam wrapped in...