Villa won 3-1 on Monday afternoon, thanks to goals from TJ Carroll, Cole Brannigan and Jamaldeen Jimoh-Aloba. City had gone ahead inside the opening minute through Matty Warhurst.
“I’m really proud,” Shan said.
“You set your stall out at the start of the competition to go as far as you can and we’ve done that, plugged away and had to dig deep at times, especially in the last round.
“I’m delighted for the boys. There was an inner belief that we could achieve something as a group this season. That’s one boxed off now and hopefully we can turn our attention to the league campaign and get over the line and win that too.”
On the big attendance, he added: “I wasn’t fortunate enough to have a career as a footballer, but I’ve stood on the sidelines with big crowds. I’ve stood here for West Brom against Villa and the only thing I can share is that you do zone-in and go into match mode.
“Some players may have crumbled under the crowd, and I think we started that way. But the crowd were brilliant for them and gave them that lift.
“They got behind them thoroughly.”
Ideal career kickstart
Over 25,000 fans attended on the day at Villa Park.
Shan also said: “It just shows the progress of the club, not just the Academy.
“What the club has done to advertise the game today and get people through the door is fantastic. The club is going from strength to strength in the right direction.
“It’s a feather in the cap for the Academy, but ultimately – and Mark Harrison just spoke to the players – it’s about players getting careers.
“We’re a firm believer that success breeds success, so hopefully this run can kickstart some careers in the next 18 months to two years.”