The biggest win for the country since a 6-0 victory in 2006 means that Gordon Strachan’s side move onto 10 points in the group table.
Bannan was delighted to see the side get a convincing victory particularly after finding themselves on level terms.
"We've came out the other end winning the game like we should have,
"You just want to win the game comprehensively and I think after they scored that shook us into life a little bit."
The midfielder, who took his place on the bench alongside club team mate James McArthur, was delighted to see the side cope with a new look three man defence.
"It's completely different to what we're used to, they came here to frustrate us and it's a bit of a shock as we're not used to that.
"It probably took time to get used to the formation and get used to the way they were setting up.
"In the end, when we figured out how to get in behind and how to hurt them, we did well and there could have been more goals.
Saturday saw Joe Ledley and Wayne Hennessey both in the starting line-up for their 3-0 victory in Israel.
The result meant Chris Coleman’s side went above their opponents to the top of the group.
The visitors had the better of the first half in Haifa and took a deserved lead as Aaron Ramsey headed in from Bale's flick-on just before the break.
Bale doubled the advantage with a superb, swerving free-kick from the edge of the area soon after the restart and finished well from close range for the third of the night to send his side two points clear in group B.
Hennessey made a crucial save on 76 minutes when his side had a two goal advantage as he reacted well to a cross from the right to get in ahead of Tomer Hemed and be first to the ball.
Ledley had to leave the field early in the second half through injury but after the match posted on twitter his delight at the result.
‘Great team performance from the boyos gotta keep going. Fans were fantastic again see you all in June’#teamwales
Kwesi Appiah was named in the Ghana side that suffered a 2-1 defeat to Senegal in an international friendly played at the Stade Oceane in Le Havre.