Lambert is delighted to see the midfielder flourishing under Ralph Hasenhuttl.
“Prowsey is one of the best, if not the best, set-piece takers and strikers of a ball I've come across," said Lambert.
“It's great to see he's had a new lease of life and been given a green light to get forward.
“I've always said he should be scoring free-kicks to get his confidence and it's brilliant to see he's hitting the back of the net now.
“With his technique he should be scoring at least five to ten goals a season.
“Under the new manager you can see the enjoyment and hunger and desire is back and hopefully he can push on again."