The Ticas controlled the match from the opening whistle with the outstanding Raquel Rodriguez Cedeño coming close twice early.
In the 14th minute, Acosta would net her first goal after a brilliant run through the Nicaraguan defense.
Seven minutes later, Acosta completed her brace off an assist from Daphne Herrera.
A precise free kick by Katherine Alvarado in the 26th minute made it 3-0, while talented veteran Shirley Cruz completed the score line ten minutes after the interval.
The Costa Ricans went a perfect 5-0-0 in the tournament, scoring 27 goals and conceding only one.
Guatemala defeated Panama 5-3 for the bronze medal.