The Dons were rarely troubled by their visitors and went ahead just before the half-hour thanks to Jonny Hayes' cool finish.
Christian Ramirez added a second with a bullet header on his cinch Premiership debut after the break.
"It was a great performance, especially first half. Performing strongly at home bodes well for the season. As a standalone, it was an exceptional performance," Glass said.
"The players looked very assured in their choices which comes down to decision-making and the players stood up to the physical challenge and kept their discipline.
"We can't ask any more than that. We've got to be able to cope with that and our group look like they can."
Glass did feel one tackle from Charlie Mulgrew on Funso Ojo overstepped the mark.
He said: "The challenge on Ojo looked like a player who knew what he was doing and I felt it was worthy of a yellow card. I don't know how that will affect Funso for the European game later in the week."
United boss Tam Courts praised the influence of the fans, who provided an intimidating atmosphere at Pittodrie, but was disappointed with the goals his side conceded.
"It was great in terms of seeing the fans back in, but the overriding feeling from me is one of frustration that Aberdeen didn't have to work too hard for the goals.
"It's not something that you can normally accuse our team of. We probably looked passive because we had a good shape and structure but we were guilty of sloppy play and gifting it back to Aberdeen. We looked dangerous when we did string some passes together.
"I'm disappointed we haven't been able to play better for longer in the game and we're not accustomed to losing goals sloppily, so it's quite frustrating."
The United players were incensed with the officials after Hayes' opener, feeling the Irishman was well offside, but Courts admitted: "We had the benefit of seeing the opening goal back at half-time and it was a good decision - Jonny was actually onside, so it's a good goal and the correct decision."