chocolate fondue vs fondu

chocolate fondue and fondu both are nouns.

Word	Noun	Adjective	Verb	Adverb
chocolate fondue	Yes	No	No	No
fondu	Yes	No	No	No

As nouns, fondu is a hypernym of chocolate fondue; that is, fondu is a word with a broader meaning than chocolate fondue:

chocolate fondue: fondue made of chocolate melted with milk or cream for dipping fruits
fondu: hot cheese or chocolate melted to the consistency of a sauce into which bread or fruits are dipped

Other hypernyms of chocolate fondue include fondue.

chocolate fondue (noun)	fondu (noun)
fondue made of chocolate melted with milk or cream for dipping fruits	hot cheese or chocolate melted to the consistency of a sauce into which bread or fruits are dipped
	cubes of meat or seafood cooked in hot oil and then dipped in any of various sauces