Still not sure if Hiei is going with it to be nice or she just has horrible taste
Her expression in the previous panel matches Haruna's and Kirishima's, so she's just being nice.
T-that looks really tasty! As expected of onee-sama...!I'm studying Japanese cuisine for the Admiral's sake!Oh, Kongou Nee-sama, are you cooking?The pinnacle of Japanese culinary arts is SUSHI!Hiei Nee-sama's going with it!?Therefore, behold my original creation: the curry sushi!!Wow! Such passion for learning!