Brittney Griner tallied 22 points, while DeWanna Bonner and Candice Dupree each had 14 for Phoenix, which scored 18 consecutive points between the third and fourth quarters to take control.
The Mercury, who advanced to the WNBA Finals for the first time since winning the championship in 2009, will face either Chicago or Indiana Sunday night at US Airways Center. Those teams tussle in Game 3 of the East finals Wednesday night. Phoenix's second WNBA title came against the Fever in 2009.
The Mercury, who were swept by Minnesota in last year's West finals, dominated the fourth quarter Tuesday night.
Minnesota, which had been to the previous three title series, winning twice (2011, 2013), got 21 points from Seimone Augustus and 20 from Lindsay Whalen.
Maya Moore's layup tied the game at 67-67 for Minnesota with 1:25 left in the third quarter, but Taurasi countered with a jumper and made a shot from beyond halfcourt to cap the period.
Phoenix then scored the opening 13 points of the final quarter, capped by Griner's turnaround bank shot with 5:12 left for an 85-67 cushion.
Lynx coach Cheryl Reeve wasn't around to see the end. She was ejected with 1:58 remaining, but not before congratulating Taurasi.
Dupree scored eight in the opening quarter, helping her team to a 28-21 lead after 10 minutes. It was 50-42 Mercury at the half.