Chadli joined Albion for a club record fee of around £13million this summer and the winger has already made an impact at The Hawthorns after starring in the weekend's 4-2 victory over West Ham United with a brace and a pair of assists.
Following the game, former Tottenham manager Sherwood praised Chadli by expressing his surprise at the decision of Spurs boss Mauricio Pochettino to allow the Belgian international to leave this summer.
"I think he's a great signing for them, he gives them a little bit of guile. I had him at Tottenham, Nacer - he affects the football match, he can assist and he can score and I was very surprised that Tottenham let him go to be perfectly honest.
"He will get 10-plus goals for West Brom. They could be crucial for keeping them in the division. He was never missing [the penalty], never in a million years was he missing it.
"I think it's the first penalty he's ever taken, certainly in England, he never took them at Tottenham, but this is going to add to his tally."