On 18 November 2006, Kandol scored an injury time winner against Rochdale at Underhill to complete his hat-trick that also saw Barnet win their third consecutive league game. Kandol's impact for Barnet saw him topping up the chart as the top scorer in F.A. Cup with 6 goals to his name, he highlighted himself by scoring by lobbing the goalkeeper from the halfway line against Cardiff City and a header to take them out of the cup, followed by another two against Cheltenham Town but his best performance came from Elland Road where he scored a powerful header. A string of good performances attracted the attention of several Championship clubs such as Crystal Palace, Cardiff City, Watford, Hull City and Leeds United. Whilst at Barnet in 2006, Kandol was sent to prison for 13 weeks for a series of driving offences.
After scoring 18 goals from 21 games for Barnet at the start of the 2006–07 season, Kandol joined Championship club Leeds United in a two-month loan deal on 23 November 2006. He made his debut two days later as a substitute replacing Robbie Blake in the 2–1 victory over Plymouth Argyle. His full home debut came with a debut goal in front of his new fans against Barnsley. When the January 2007 transfer window opened, his move to Elland Road was made permanent by Dennis Wise for an initial fee of £320,000. After Leeds were relegated to the third tier of English football for the first time in their history, Kandol scored a last-minute winner against Tranmere Rovers in the opening game of the 2007–08 League One season. He formed a successful strike partnership with Jermaine Beckford in the first half of the season, winning him player of the August and September month award but loss of form and the arrival of Dougie Freedman meant Kandol lost his place in the starting eleven despite scoring 15 goals, as Leeds went on to reach the playoffs. He was a second-half substitute as Leeds lost 1–0 in the final against Doncaster Rovers.