Patric Hornqvist had a goal and two assists, and Matt Murray made 22 saves for the Penguins (6-2-0), who have outscored their opponents 23-11 during the winning streak. Each of the five wins has come without injured forwards Evgeni Malkin (lower body), Alex Galchenyuk (lower body), Nick Bjugstad (lower body) and Bryan Rust (upper body).
"I think every guy that's coming back from injuries is going to get in line and play the same way," Letang said. "We're trying to establish an identity for our team. I think that's what we're starting to build on right now."
WATCH: [All Stars vs. Penguins highlights]
Roope Hintz and John Klingberg scored, and Anton Khudobin made 29 saves for Dallas (1-7-1), which has lost five in a row and been outscored 17-7 in that stretch.
"You can't drive passion into people," Stars coach Jim Montgomery said. "You can try everything. You can try motivational tactics. You can try everything, but it has to come from within. Ultimately, if there's a puck between you and I, I'd bite your leg off to get it. That's the attitude you have to have. Anton had that competitive spirit tonight that we need to permeate throughout our lineup."
Letang, who has 10 points (four goals, six assists) in eight games, gave the Penguins a 2-1 lead at 6:34 of the third. He stick-handled around Joe Pavelski and waited for Tyler Seguin to slide by in an attempt at a blocked shot before shooting under Khudobin's right pad.
"Not much was working, as far as results," Seguin said. "[Pavelski] goes and slides. Then, for whatever reason, I go and slide too, and the guy just walks in on a breakaway. That just can't happen."
Hornqvist made it 3-1 when he deflected a shot from Brian Dumoulin at 10:20 of the third before Klingberg cut it to 3-2 with a wrist shot from along the right boards at 12:01.
