Is “beaten egg” countable or uncountable?
I understand that many English words used as a noun can be used as both countable and uncountable, and whether the word is used as countable or uncountable depends on how the word is used in a sentence.
Having said that, I still find it confusing.
My understanding is that the word “egg” is countable when it refers to an individual egg while the same word is uncountable when it refers to “beaten egg” as a substance.
But I often see not only “into beaten egg” but also “into a beaten egg” in online recipe books or news articles.
Moreover, for example, when the beaten egg consists of three eggs, it seems acceptable to say, “Add three beaten eggs”; By googling, I see the phrase/sentence “add three beaten eggs” in quite a few recipe books.
So, back to my question; Is “beaten egg” countable or uncountable?