Evgeni Malkin had five assists, Sergei Gonchar had three assists and Jarkko Ruutu scored on a penalty shot goal for the Penguins, who were 5-for-9 on the power play.
Recchi, who also added an assist, recorded the seventh hat trick of his career in a span of 16:57, starting late in the first period. His most recent was March 4 against Carolina, where he was traded five days later before re-signing with Pittsburgh as a free agent in the off-season.
The Penguins enter the all-star break 3-0-1 in their last four game and in a three-way tie for the eighth and final playoff position in the Eastern Conference.
Toronto's Jeff O'Neill scored the first goal 3:19 into the game on a power play.
But from there it was all Pittsburgh as Jordan Staal scored the first of seven straight goals 1:31 later. He tipped in a pass from Malkin while going hard to the net. Malkin has five goals and seven assists during a five-game point streak.
The Penguins took a 2-1 lead with 11:30 left in the first on Ruutu's penalty shot.
Ruutu, who hadn't scored since the season opener, was pulled off his skates by Carlo Colaiacovo on a breakaway against Toronto goalie Andrew Raycroft. On the penalty shot, Ruutu faked a forehand shot to freeze Raycroft before tucking the puck into the net with the backhand.
Recchi made it 3-1 with 2:32 to play in the opening period when Ryan Whitney's centring pass deflected off his skate and into the net.
Recchi's second of the game and 13th of the season came midway through the second off a pass from Crosby. His third came at 14:25 of the second from Crosby and Gonchar. That was Recchi's 498th career goal and his 1,306th point in his 1,302nd NHL game.
Crosby added a 5-on-3 goal 4:02 into the third against backup goalie Jean-Sebastien Aubin, an ex-Penguin, and Michel Ouellet added a power-play goal with 8:52 to play.
Brendan Bell scored a power-play goal for Toronto with 6:16 to play before Ryan Malone - off a pass from Malkin - scored his seventh 1:01 later.
The Penguins matched their season-high in goals - done twice against Philadelphia - and the six-goal margin of victory matches the 8-2 Pittsburgh win over the Flyers Oct. 28.
Notes: Pittsburgh is 3-for-4 on penalty shots this season. RW Nils Ekman scored Dec. 7 against the Rangers, Staal converted one Oct. 21 versus Columbus and Staal's attempt was saved by the Rangers' Henrik Lundqvist Nov. 25. ... Ouellet has a five-game point streak, Recchi has a four-game point streak and Whitney has an assist in each of his last five contests. ... Toronto had won seven in a row in Pittsburgh until a 4-1 defeat here Dec. 29.