"C на Дне рождении была очень вкусной"
"Еда на Дне рождении была очень вкусная."

Apparently both are correct. But the first one looks wrong to me; вкусной is the ending for genitive, dative, instrumental and prepositional. Isn't it supposed to agree in gender number AND case, with "Еда"?

Any advice welcome!

Rich B