Do you say "my favorite food is apple" or "my favorite food is apples"?

I would say “apples are my favorite food.”

Personally I just choose what feels and sounds “right”.
But if I had to come up with a justification, I would say that when I name a favorite food, or beverage or anything along those lines, I name a type or category, not a singular item, or even a multiple of items.

With @jca2. Apples are my favorite food.

@ragingloli unfortunately I’m not really in a position to choose because this is part of my lesson and I will have to be prepared for questioning of my decision. That’s why I need to make sure I’m doing things correctly.

The reason I’m asking is because I saw my colleague teaching her own students that “my favorite food is apple” was the correct one and she paired it with “I like apples”, without any explanation. This just doesn’t sound really right to me so I need to ask to double check. That is a lesson I already taught my own class and I avoided the favorite thing and chose to just tell them about the liking thing so that I didn’t confuse them.

My favorite foods are apples

Plural Apples

Some words we don’t quantify – you can but we typically don’t, for example, shrimp or candy. We don’t usually say shrimps or candies. You can say it but most people don’t. We wouldn’t say I want shrimps with pasta or I bought candies at the store. We’d say I want shrimp with pasta or I bought candy at the store.

A word like apple, we do quantify, apples. Apples are my favorite food.

My favorite food is an apple, or my favorite food is apples.

Or, apples are my favorite food.

I might say “My favorite food is an apple,” but “Apples are my favorite food” is also correct and idiomatic. We wouldn’t use “apple” as an aggregate like “fruit.” The closest we might come, sounding a bit stilted, is “The apple is my favorite.”

@SergeantQueen, in this context, do you really think you would say “foods”?

^^^what she said!
What is aggregate¿

That was my first thought