A first-half strike from Sone Aluko was matched by Hull's Evandro just after half-time, but further efforts from Chris Martin, Sessegnon and Stefan Johansen capped a dominant display by the Sky Bet Championship side.
Fulham go through to the fifth round of the FA Cup for the first time since 2011, and Jokanovic said teenager Sessegnon proved he has the quality to go a long way in the game.
Jokanovic said: "Of course I am pleased with him
"He has showed the right personality, he is only 16 years old but he is 100 per cent going to be in the highest level soon but I am enjoying working with him
"I want to use him in my squad for a long time, he will shine in the future."
The Fulham manager added: "Our general performance was very good.
"We have tried to move the ball around against a strong Hull who showed in midweek how good they can be, and what they have changed."
Although Hull tested Manchester United almost to the limit on Thursday in their EFL Cup semi-final second leg, Fulham were comfortable winners against the Tigers.
"We deserved this victory," Jokanovic added
"We have to be satisfied when we beat a Premier League side.
"Look where we are, we are in the next round and we are fighting (for a play-off place), we are fighting hard which is important."
Premier League side Hull find themselves out of both cup competitions after back-to-back disappointments, and manager Marco Silva believes they need to swiftly show a positive reaction.
The visitors were awarded two penalties with only minutes left of the match but Abel Hernandez missed both , which could cost him the spot-kick responsibility
Silva said: "We will see
I need to think about it
It is a decision I will take for the next penalty
"It is not easy when we lost like we did today
Fulham deserved it
We did not start well, we were out of focus
"They started stronger, faster
Our concentration was not there at some moments, the first goal is a good example.
"We need a reaction
We will do our work, we lost this game and they deserved to win.
"Not everything is wrong
I will analyse the game with the players so we can prepare."
Source : PA