Tortorella blamed the goal on successive mistakes by the Golden Knights.
"The frustrating part for me is they don't earn their winning goal," he said. "It's not so much the turnover and Carter makes a great save, but just after that we make another mistake and we leave the front of the net. … It's just for free. That's a hard one for me in the third period."
Ehlers scored a length-of-the-ice empty-net goal at 19:05 for the 5-3 final.
"We tied it up, we were playing some good hockey and had plenty of chances to go up ahead in the game," Vegas forward Colton Sissons said. "Just couldn’t find a way. It was unfortunate."
Stankoven scored from the slot at 1:06 to make it 1-0. Blake made it 2-0 at 3:28.
Stone cut it to 2-1 at 7:22 with a breakaway goal.
Staal scored a power-play goal at 12:48 off a rebound from the slot to make it 3-1.
"I've been telling the guys to get to the hoop for I don't know how long, years," Staal said. "Good things happen around there."
Karlsson scored on a one-timer from the left face-off circle at 4:22 of the second period to cut Carolina's lead to 3-2.
Howden made it 3-3 at 17:08 with his NHL-leading 14th goal of the postseason.
But Staal came through again when it mattered, and the Hurricanes rode it out to turn a best-of-7 into a best-of-3.
"It's a good time to get hot," Staal said.
NOTES: Hurricanes goalie Frederik Andersen was a healthy scratch. He started the first 16 games of the playoffs. … Bussi became the third goalie in the expansion era (since 1968) to make his first career playoff start in the Stanley Cup Final. The others are Andrei Vasilevskiy (Game 4, 2015) and Jussi Markkanen (Game 2, 2006). Bussi became the third goalie in NHL history to make his first career playoff start in a Stanley Cup Final and pick up a win. The others are Hank Bassen (Game 2, 1961) and Alfie Moore (Game 1, 1938). … Staal (37) is the oldest player to score at least two goals in a Stanley Cup Final game since Mark Recchi did it with the Boston Bruins in 2011, when he was 43 years old.