The England international scored an impressive 31 goals in 51 games in all competitions for the north London side in the 2014/15 season.
However, the 22-year-old failed to find the back of the net in his opening eight games of the season for Mauricio Pochettino’s side.
Former Republic of Ireland defender Cunningham was never in doubt that Kane would rediscover his goal-scoring form despite his slow start.
“I was never worried about Harry Kane,” Cunningham told Newstalk.
“He was a top-class player. His football intelligence was obvious.
“In terms of his technique, his vision, his movement, you could tell it was only a matter of time.
“There was never a doubt about Harry Kane.”
The reported Manchester United target has scored two goals in his last four games in all competitions for the Lilywhites.
The England striker has scored 15 goals in 30 appearances in the Premier League, the League Cup and the FA Cup this term.
The Tottenham striker was named the PFA young player of the year after his impressive breakthrough season at White Hart Lane.
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