The 28-year-old Sierra Leone international came off the bench for the final half-hour at Carrow Road and helped secure what could prove a vital Barclays Premier League victory with a powerful header to cancel out Leon Osman's first-half opener.
Captain Grant Holt then netted a dramatic winner in stoppage-time.
Kamara - who left his homeland aged 14 before eventually migrating to the United States from Gambia and going on to play football at college - had an unsuccessful trial at Stoke in December.
While Hughton was not able to watch the pacy, 6ft 2ins forward personally, the Norwich manager saw enough to convince him to give Kamara his opportunity in the English top flight.
"The ideal scenario means you have been able to go and see the player, but I was not able to see him play live, although our chief scout had," said Hughton, who could yet make a permanent move for Kamara at the end of the season.
"I have only seen him on DVD, but you have to trust judgements of your scouts and the people who are giving you references."
- Sports & Recreation