The League Two promotion hopefuls sprung a shock at Villa Park, with two late goals securing a 2-1 comeback victory over Unai Emery's Premier League side.
Villa, which had Leander Dendoncker sent off for a foul that led to Jamie Reid's equaliser from the spot before Dean Campbell's 90th-minue winner, has lost eight consecutive FA Cup games.
But the host's woes were far from the mind of victorious boss Evans, who shared a telling snippet from a conversation he had enjoyed with his employer.
"It is really special," he told BBC Sport. "The chairman just said to me it's the greatest day in his life and he's been with the club for 26-27 years.
"It's a fantastic day for the town but we'll not kid ourselves; this is a fantastic football club and we'll enjoy the moment and these guys have treated us absolutely fantastic since we walked into the building today.
"We'll know to be humble and get on with our jobs for Saturday."
It is indeed back to reality for the fourth-tier club, which heads to Harrogate next weekend as its promotion push continues.
For Villa, which welcomes Leeds United on Saturday, it is a stark reminder that, despite making strides since Emery's appointment in October, it has a long way to go.
The winning goal came from a short corner as the 10-man hosts failed to close down Campbell, who struck a low shot beyond Robin Olsen.
An apologetic Emery, who made eight changes and saw his men take the lead through Morgan Sanson, said: "They were so excited to try and surprise us in the corner and they did it.
"I'm really sorry for the supporters. It's a process we are [undergoing] here and I want to create [something].
"It was really so, so disappointing. We can feel because at the end we lost everything we created in the 80 minutes."
It is the first time since 1964 that Villa has lost to a fourth-tier outfit while in the top flight.