What noun in English would be idiomatic to refer to an opportunity to participate in an activity that one is very good at and in which he normally can show his skills.
I am especially after a noun that would follow smoothly right after the word "real". Like here:
His conversational skills are not great and his passive vocabulary is
rather limited. This, however, somehow doesn't stop him from
participating in our small in-class discussions. And his real _______
is skits. That's when he does his best and shows off all his talent to
the whole class.
The word "forte" should suit your needs. It is idiomatic. See these corpus search results. – (Wehage) Note the American audio is incorrect at that link. It is pronounced "fo(r)tei" in both British and American.
Alternatively, in British English - "strong suit"
n. 1. A quality, activity, or skill in which a person excels: Foreign policy was the president's strong suit. (AHD via TFD)