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soft and flaky (pie, potatoes, squash, etc.); fluffy; crumbly; fresh-baked; fresh from the oven
being pleased with oneself; beaming happily; chuckling to oneself
焼き芋がほくほくで美味しい。
The roasted sweet potato is fluffy and delicious.
ほくほくのじゃがいもを食べた。
I ate fluffy potatoes.
ほくほくしたかぼちゃが好きだ。
I like fluffy squash.