Course in headquarters first off attended by European (6)

I believe the answer is:

entree

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'course' is the definition.
(course of a meal)

I can't explain the rest of the clue.

(Other definitions for entree that I've seen before include "Introduction" , "The right of admission or entry" , "The right to enter a particular sphere" , "The right ot privilege of admission" , "Dish; right of admission" .)

I've seen this clue in The Independent.

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