Traore signed a new three-year contract with Chelsea at the start of the season before being immediately loaned to Dutch giants Ajax.
The 21-year-old Burkina Faso international struggled early on with the Eredivisie club, but has found his form of late - and starred on Wednesday night as Ajax thrashed French club Lyon at the Amsterdam ArenA.
Traore had been in doubt before kickoff with a groin injury, but led his side to victory as the four-time European Cup winners made the most of their first European semi-final since 1997.
Playing in the Amsterdam ArenA for the first time since an announcement that the stadium will be renamed in honour of Ajax's greatest player, Johan Cruyff, Traore and his team-mates put in a performance that would have made the Dutch legend proud.
It also showed that this young Ajax team could be strong enough to win their first continental title since 1995.
Poor finishing and good goalkeeping combined to keep the score respectable for Lyon. After a scrappy opening in which Lyon gave Ajax little time or space on the ball, Traore put Ajax ahead in the 25th minute, leaping between a crowd of defenders to send a glancing header into the far corner from a free kick by Hakim Ziyech.
Ziyech was also the provider for Traore's second in the 71st minute.
In between his strikes, Traore created Ajax's second goal nine minutes after his first, powerfully heading a poor clearance by Lyon goalkeeper Anthony Lopes into the path of 19-year-old Denmark striker Kasper Dolberg, who calmly fired a low volley past the goalkeeper.
Amin Younes scored for Ajax in the 49th minute and Mathieu Valbuena replied with Lyon's consolation goal in the 66th.
The winners of Ajax and Lyon's tie will face either Manchester United or Celta Vigo, with Jose Mourinho's side due to face the Spanish club in the first leg of their semi-final on Thursday night.
Additional reporting by Reuters.