The Americans outscored their opponents 26-0 in five games over 10 days and earned some measure of revenge against Canada, which held the United States to 0-0 draw in the knockout round in 2010 and then prevailed on penalties to make it the only U.S. women's team to fail to qualify for a World Cup.
Both teams already had assured themselves of a berth in this year's U-17 Women's World Cup with semifinal victories on Thursday.
The result was the 14th victory in 15 matches for the United States in the CONCACAF finals, while Canada lost for only the third time in 15 games.
The United States had the better of play for most of the first half, while Canada controlled the ball for more of the second half, especially the final 10 minutes.
However, besides Munerlyn's goal, only sporadic chances tested either goalkeeper. Canada put on a late push in the final 10 minutes, but managed only two shots on U.S. keeper Jane Campbell.
The best opportunity outside the goal came in the 34th minute when Munerlyn volleyed Summer Green's cross off the right post.
The Americans had the better of the very early play and went ahead in the 21st minute when Maddy Bauer drove a ball from within her own defensive third to Green, standing on the edge of the edge of the center circle in the Canadian half.
Green used a deft back heel to send Munerlyn down the middle of the Canadian defense, where she outran Rebecca Pongetti and fought off the shoulder challenge of Lindsey Agnew before dribbling into the penalty area and chipping a soft shot over goalkeeper Kailen Sheridan from the penalty spot.
The Americans appeared in control for the rest of the half and had the better possession to start the second until Canada sent more players forward as the final minutes closed.
Its best opportunity came when Madeline Iozzi crossed into an unmarked Valerie Sanderson in the middle of the penalty area. Sanderson chested the ball down and was able hit a left-footed shot but directly into Campbell.
"We could have done much better job of holding ball in the second half. We had a tough game in the second half," U.S. coach Albertin Montoya said. "We definitely need to continue working on holding the ball. We were fortunate there at times."
The Americans prevailed by stacking its penalty area and blocking nearly all of Canada's shots and not requiring any dramatic saves from Campbell.
The United States, Canada and Mexico leave only two berths open in the 16-team U-17 Women's World Cup field.
Besides the CONCACAF teams, China, Japan, North Korea, Gambia, Nigeria, Ghana, New Zealand, Brazil, Uruguay, Colombia and host Azerbaijan all have qualified, with only Europe's last two entrants to be decided.