Both of Prescott's scoring passes went to Amari Cooper, who led the Cowboys with six catches for 88 yards.
Josh Rosen, who was acquired in the offseason after starting 13 games last season for Arizona, started for the first time for the Dolphins (0-3) and passed for 200 yards. He was sacked three times by the Cowboys, who entered the game with just two sacks in their first two games.
The Cowboys (3-0) got on the scoreboard on their first possession on a 28-yard field goal by Brett Maher. Dallas added to its lead via a 5-yard touchdown pass from Prescott to Cooper with 5:57 to play in the first quarter.
But the rest of the half belonged to the Dolphins, who had been outscored in their first two games by a combined score of 102-10.
Miami clawed back to within 10-6 at halftime, first driving 72 yards in 10 plays to a field goal by Jason Sanders with 58 seconds remaining in the first quarter. The Dolphins had to settle for another Sanders field goal, this one from 33 yards out at the 5:48 mark of the second quarter, after Preston Williams dropped a potential TD pass from Rosen in the end zone.
The Dolphins then moved into the red zone in the final minute of the half before Kenyan Drake fumbled at the Dallas 7-yard line, erasing Miami's chance to take the lead before the half.
Dallas opened the third quarter with a bang, moving 75 yards in five plays to the second Prescott-to-Cooper TD hook up, this one from 19 yards out.
Prescott strolled into the end zone for a 8-yard TD run with 3:30 to play in the third quarter to push the Cowboys' lead to 24-6 before Pollard got loose for a 16-yard scoring run with 3:50 remaining in the game.
--Field Level Media