Following a first leg in which Derby took a narrow 1-0...
Sessegnon scored the opener and delivered the corner for Denis Odoi's victor as Fulham overcame a 1-0 first leg deficit and earned themselves a first trip to Wembley in 43 years.
Fulham, who have only lost twice since December 16, will now meet either Aston Villa or Middlesbrough at the national stadium on May 26 and are 90 minutes away from a first return to the Premier League since 2014.
Fulham will be making it to Wembley for the first time in 43 years, where the face the victor of the game between Aston Villa and Middlesborough.
For Fulham - bidding to regain their Premier League status after a hiatus of four seasons - it is an historic moment as it was is the first time they have won in eight play-off matches.
A stunning save from Scott Carson to deny Aleksandar Mitrovic kept the score at 0-0 at the interval, but Sessegnon punished a rare piece of slack defending two minutes into the second half, collecting a loose ball in the box and rifling high into the net.
After a plethora of first-half chances went by the wayside, Sessegnon broke the deadlock in the 47th minute when he lashed home from close range and then set up Odoi with an in-swinging corner.More news: Four children become orphans in Surabaya, Sidoarjo bombings
"To get to half-time at 0-0, we felt that we had to step out a bit more and be more proactive".
The hosts' efforts to wrap things up in normal time saw Mitrovic let fly from distance before Kamara flashed a shot just wide of the post.
"They were two very, very poor goals for us to give away".
"This club needs this kind of happiness", said Jokanovic, "After 43 years we will play at Wembley and it is an important achievement for us".
When asked how he deals with being in the spotlight and the pressure that is put on him, he added: 'I just try to play my own game.
'I just get my head down and work hard for the team'.