The England international scored Newcastle's opening goal and assisted the third, contributing significantly to the win at St James' Park.
Mourinho approached Gordon after the match, telling him 'You're too much,' which Gordon considered a significant compliment.
Gordon's goal was his fourth in three Champions League games this season, helping Newcastle climb to seventh place in the table.
Newcastle manager Eddie Howe lauded Gordon's direct play and athletic effort, while Gordon also praised teammate Nick Woltemade's contribution to the third goal.