Buffalo cut San Jose's lead to 2-1 on McCabe's first goal of the season at 1:35 of the second period.
"When special teams are struggling as much as it is and power plays are struggling you've got to go back to work and go back to simplicity," McCabe said. "Look at their power play, it was nothing special, they're getting pucks to the net and bodies to the net and it creates chaos and it's tough to defend."
Couture increased the lead to 3-1 at 4:54 of the third period when he knocked a Kane rebound into a wide-open net.
Pavelski scored on the power play at 11:49, making it 4-1, and Couture completed the hat trick with an empty-net goal at 18:13 for the 5-1 final score.
The Sharks took leads into the third period of their two previous games but lost 3-2 in overtime to the New York Rangers on Oct. 11 and 3-2 to the New Jersey Devils on Sunday.
"We wanted to make sure we aren't going to be a team that lets third-period leads slip away," Kane said.