語る and に particle

Question

コロッケ一つにこんなに熱く語るなんて

I'm confused by this sentence, 語る usually uses を to talk about something, so what does this mean?

For context the person in this manga is very enthusiastic about croquettes but I do not understand the ni particle here as 語る is a transitive verb if you are going to talk about something. ''talking to a croquette'' sounds unnatural as well as a translation but I don't know.

[2nd EDIT] I think I have come to the conclusion that 一つに might mean ''for one'' as a combination of the particle and the word.

''To speak enthusiastically for one croquette''

Let me know if I am wrong but that's the only thing that makes sense to me

Answer 1

Interestingly, while コロッケに語る feels 100% ungrammatical to me, コロッケにこんなに熱く語る suddenly sounds acceptable. So somehow the adverb こんなに熱く is what makes に possible here. Besides, it's 100% natural to say コロッケに熱くなる. Therefore, I suppose this に was chosen as a marker for the cause of a psychological reaction, and に is acceptable here because it's a particle associated with 熱く(なる). Canonically speaking, it would be better to put this sentence as コロッケ一つにこんなに熱くなって語るなんて, but the original sentence already makes sense to me.

ひとつ/ひとり/etc is sometimes used like a suffix to add a sense of "just one". For example, リンゴひとつでお腹いっぱいになった means "I became full with just one apple", and 雑魚一匹を倒すのに時間がかかった means "It took a long time to defeat just one weak enemy". The nuance of "just" is rather explicit when ひとつ/一匹 is used in this way.