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crisp (not moist or juicy); crunchy; flaky (as in pastry)
crunching sound (of walking on snow, frost, sand, etc.)
doing skillfully and efficiently; doing quickly; proceeding smoothly
天ぷらの衣がさくさくだ。
The tempura batter is crispy.
さくさくのクッキーを焼いた。
I baked crunchy cookies.
パイ生地がさくさくして美味しい。
The pie crust is flaky and delicious.