in grammer, it's all right, you can use it.
but in oral we don't say it this way, cos favorite usually means "the best". we usually just say ".....is my favorite"

favorite means 'the best liked'. However you have a few favorites, the few types of ice-cream flavor you like best.
So, you have to say 'one of my favourites' and not 'one of my favourite'.

Sorry, for the second part of my first answer, I was using the British spelling 'favourite' for 'favorite'.

one of my favorites means u have a few things which is in favor and it is one of them.... in fact, u can say it...