Lasse Kukkonen was born September 18, 1981 in Oulu, Finland. The fifth round, 151st overall selection of the Chicago Blackhawks in the 2003 NHL Entry Draft, Kukkonen honed his skills in Finland before making his NHL debut in 2003-04.
Upon his arrival in North America, Kukkonen spent the majority of his rookie season with Chicago's AHL affiliate in Norfolk while seeing action ten games with the parent club.
Kukkonen became a regular in the Blackhawks line up in the 2006-07 season appearing in 54 games with the club. Despite his increase in ice time, Kukkonen was traded to the Philadelphia Flyers one day prior to the NHL trading deadline.
On the international stage, Kukkonen represented his homeland at the 2005 World Championship.