Mings was targeted by sections of the home support with racist abuse in the early stages of his England debut in Sofia, with television cameras showing the centre-half turning to ask the assistant referee if he had heard the vile chanting.
That would lead to the first of two breaks in play as England's 6-0 victory in the Euro 2020 qualifier was overshadowed by the unacceptable behaviour of a certain section of home fans.
Smith, though, expressed pride in Mings' display for the Three Lions as well as how he conducted himself in the face of discrimination.
"The fact that he's come back here, trained and got on with things as normal, not really said too much about it, I can only sing his praises," Smith said.
"When we go and look at players and speak to them, we know what they're going to bring football-wise, but it's that personality, character that you're looking to talk to and find out about.
"Having met him and brought him to Aston Villa on loan and then we've signed him and seen him every day, it didn't surprise me how he handled the whole situation because he's articulate, he's intelligent and he's a very good human being."
Mings has been a standout performer for the West Midlands outfit this season as they try and get to grips with the pace of life back in the Premier League.
Former Bournemouth star Mings was a key part of the Villa side that secured promotion from the Championship last season and he will be vital if they are to avoid a swift return to the second tier.
Villa are back in action after the international break when they host Graham Potter's Brighton on Saturday.