If it's not 「炒ったハゼだ」"It's a fried goby," I guess you mean "Itta hazu da." It means "I told you" or "He/she should have gone." We can't tell without kanji and context because "itta" has several homonyms.

Maybe "itta hazu" is "言ったはず". That means "I told you".

Are you sure it isn't: Itta hazu da? That means: He's supposed to have gone.

mabye one goby(fish) 一鯊だ