The 20-year-old was handed a start and needed only 13 minutes to make his mark in a sold-out Amman International Stadium, converting from a pass by Marco Asensio.
With all eyes on Ansu after doubts over whether he would make the 26-man squad, he looked lively and was off target with another couple of attempts as a Spanish side featuring several fringe players dominated.
The former world champions doubled their lead in the 56th minute when Carlos Soler dribbled into the box and set up Pablo Sarabia who made a mess of his effort but Gavi seized on the loose ball to fire home.
Youngster Nico Williams, who replaced Ansu late on, did his cause no harm with a well-taken third in the 84th minute.
Spain blotted their copybook as Jordan managed a late consolation through substitute Hamza Al Dardour after a mistake by substitute Cesar Azpilicueta.