What is "fusion-y"?
In casual contexts, people sometimes add the -y suffix to words to make non-standard adjectives or to emphasize an intrinsic characteristic of the noun. In this case, fusion is a noun, and after having -y added to the end, becomes "fusion-y" (to be of a fusion or mixture of more than one element). The speaker has done this to express that the food is a fusion or mixture of Italian and French cuisine. It is similar to the -ish suffix. Ex: The rain has stopped. It is cloudy. (Cloud + y = cloudy, standard adjective). Ex: Mix the ingredients together until the mixture becomes kind of yellowish.