Morata has 16 goals in the Premier League since arriving from Real Madrid last season, but five have come this season following a lengthy drought last campaign.
"Morata will score goals," Hasselbaink said. "He is a confidence person. He is so good at getting behind the defence and he needs to keep on doing that.
"Everybody says 'he needs to do this and needs to do that' but he shouldn't concentrate on becoming something he is not. He should embrace what he has got.
"He's not somebody who likes the contact of the centre-halves, but he shouldn't have to play like that. If he keeps on playing to his strengths I believe he will score a lot of goals."
The Dutchman also reserved praise for Olivier Giroud, who has made an impact at Chelsea since joining from Arsenal last January.
He said: "Giroud is different. He's never been an out and out goal-scorer but he makes other people around him play better which is something magnificent to have.
"Chelsea will need him during the season because there will be matches where they will need to play with Giroud up front."