Mergim Berisha scored the opening goal in the 45th minute and Aaronson, a 20-year-old acquired in January on a transfer from Major League Soccer's Philadelphia Union, doubled the lead with his fourth goal for Salzburg in all competitions.
The win also gives Salzburg manager Jesse Marsch his second straight title in the competition. The American will depart from Salzburg at the end of the season to take over German sideRB Leipzig.
"The opening goal was very important. That allowed us to apply more and more power in the second half, and we got more chances as a result. I am really pleased for the boys to have won this trophy," Marsch said.