Sessegnon marked his first Champions League start for Spurs since his move from Fulham with a goal.
Mourinho was happy with the England midfielder’s performance at Allianz Arena, although he insists the Fulham academy graduate needs to add few things to his game.
"That is the quality we know he has. He arrives always in dangerous positions and he is a good finisher," the Portuguese coach told BT Sport after Spurs’ defeat at Munich.
"He has a lot to improve. He lost too many individual duels and he has to learn how to use his body.
"He was playing experienced players and has a lot to develop, but the potential is there."
Sessegnon scored on the 20th minute mark to become Tottenham’s youngest scorer in the Champions League, and he hopes this is the beginning of his rise in North London.
He said: "I felt good. I was a bit tired at the end but to get the goal on my first start is a special moment.”
"Definitely this can help kick-start my Tottenham career. I was injured when I got here and it was difficult at the start.”
"I am back in the team now and just want to get more minutes under my belt.”