Iginla has points in eight of the last nine games (five goals, seven assists) and leads the Flames with 11 goals. Tanguay has 10 assists in the past six games.
"We knew we were going to click at some point and now it's starting to come," said Tanguay, acquired from Colorado last June in a trade for defenseman Jordan Leopold.
The tandem exhibited their newfound chemistry on the opening goal 7:38 into the first period.
On a power play, Tanguay feathered a pass across to the Flames' captain, who one-timed a 40-foot slap shot past Nikolai Khabibulin.
"That pass he gave me on the first goal, my eyes lit up. It was right in the middle of where you want it," Iginla said.
He shot it right where he wanted, too.
"If you give Iggy the puck in the slot like that, he's not going to miss too many times. That shot was so hard it almost went through the net," Tanguay said.
One night after their six-game winning streak was snapped in Edmonton, the Flames returned home and got goals from three lines before Iginla's empty-netter with 37 seconds remaining.
Matthew Lombardi and Tony Amonte also scored for Calgary, which won its fifth straight at home. Kristian Huselius had an assist to extend his points streak to five games (four goals, two assists), and Tanguay had two assists for the fifth time in six games.
"The win feels good, especially after last night and playing back-to-back," said Iginla, whose seven-game scoring streak was snapped Tuesday night.
"When you play back-to-back, you never have the same jump you had the night before. We knew we had to minimize their chances and we felt we did a good job of that," he added. "On the offensive side, we took care of our chances. It's nice to win the second one of back-to-back games."
Tuomo Ruutu scored for Chicago. He has a goal in each of the Blackhawks' last three games after missing the first 10 games of the season with a sprained knee.
The Blackhawks are 1-2-1 on their five-game road trip, which ends Friday night in Edmonton.
Calgary led 2-1 after the first period and the score remained that way until Amonte scored at 8:46 of the third.
Byron Ritchie slid a pass across the top of the crease to Amonte, who knocked it behind Khabibulin.
Entering the night with a 15-2-2 career record against Calgary, Khabibulin got the start for Chicago and dominated the Flames early on.
Thanks in part to three consecutive power plays to open the game, Calgary piled up a 9-1 edge in shots before the game was 7 minutes old. The score remained 0-0, however, as Khabibulin stymied the Flames time and time again.
The Flames eventually broke through, converting their fourth man advantage.
"When you compound penalties like that, you overplay certain players and it takes you time to get the momentum back," Chicago coach Trent Yawney said. "That wasn't our plan but it happened because we kept turning over the puck and that's been our nemesis all year."
Calgary increased its lead to 2-0 at 14:57 of the second, taking advantage of a Chicago turnover deep in its own end.
Patrick Sharp's attempted breakout pass was intercepted by Huselius, who curled back toward the net and fed a pass over to Lombardi, who one-timed the puck inside the goal post from a sharp angle.
The two-goal lead lasted just 39 seconds.
Lasse Kukkonen's shot from the blue line took a fortuitous carom off Carl Corazzini in the slot and bounced to an uncovered Ruutu at the side of the net, who zipped a backhand over Kiprusoff's shoulder.
Khabibulin finished with 36 saves in his third game since returning from a broken finger.
"That was a pretty big game for us and we didn't get that win," he said. "They lost a big game last night and they wanted to come back and win, and for some reason we didn't play 60 minutes."
Calgary D Andrei Zyuzin did not play after taking a shot off his foot Tuesday night in Edmonton. Rookie Mark Giordano took his spot. ... Corazzini made his season debut after being recalled from Norfolk (AHL) on Monday. ... The Flames improved to 6-0-0 when leading after the first period. ... It was Kiprusoff's 76th win for the Flames, tying him with Phil Myre on the franchise list. Kiprusoff trails Mike Vernon (259), Dan Bouchard (168), and Rejean Lemelin (144).