They are now 12 points clear of second-placed Exeter after 15 rounds.
However, they were looking defeat in the face when down by 12 points with only six minutes remaining. A penalty try was followed by England prop Kyle Sinckler scoring his first try for the side to give goal-kicker Callum Sheedy a sideline conversion attempt to claim the win. He succeeded that drew praise from Lam.
"He's had some pressure kicks against England and now he's stepping up for Bristol," he told bristolbearsrugby.com.
Lam explained the method behind the side's success.
"Win or lose, we do the same system. This is why we're at the top. This is the first season of doing the same process, and that's where we get growth and our mindset.
"We showed a lot of character. I said after Saints, [Northampton] when we came back and won that it wouldn't be the last time, and this won't be either, and now it has happened a week later.
"With 10 minutes to go, we got the message on to say we have 10 minutes to win this. You have done it before, let's do it again.
"The boys know what that means; it means be detailed, stay in the system, work through and put the pressure on, and the boys came home strong scoring two tries. It was class," he said.
Former Hurricanes coach Chris Boyd's Northampton side had a rare day out, beating Worcester away 62-14 with the side in fifth place on the ladder on 41 points.
After a tough first half, the game turned in the second as they finished with nine tries.
"It was certainly nice for us not to be pulling our hair out in the last 15 minutes," he told the Northampton Chronicle.
"We've got through the middle of games and not closed them out so to finish the game in the way we did here was good for us.
"I've been on the back end of games like this in my career, and when the floodgates open, nothing seems to go right. So, it's good for the side that's got all the energy and momentum.
"It was a tough place for them to be, but good for us," he said.