In desperate conditions, the Mark Johnston-trained four-year-old turned the valuable marathon handicap into procession.
Despite being drawn out wide in stall 16, Making Miracles was smartly out of the stalls and soon in control at the front end.
Low Sun was quick to join him from stall 17 and the pair were able to dominate the race.
The Willie Mullins-trained Low Sun lost touch in the straight, but Making Miracles (16-1) kept up the gallop to win unchallenged by six lengths.
Who Dares Wins just edged out Low Sun's stablemate Whiskey Sour by a neck for second spot.
Norton said: "I was drawn 16 and they said I couldn't win from there, but I had a good, willing partner. I was able to go at the fractions I wanted to go and then it was nice and easy.
"When Ryan (Moore, Low Sun) came to me I knew I had a horse underneath me. He won nice and easy."
The veteran rider added: "It's beautiful as it was a race I wanted to win, so I'm happy. No I'm not (going to do a Ruby Walsh and retire) - I've only just started!"
Johnston said: "Franny was cantering round in front. We thought beforehand, as we have been talking about draws all week, that it seemed you would struggle to win with double figures in the Chester Cup.
"I saw him get across without too much effort really and he was able to relax in front, never going that strong a pace.
"Clearly anybody who was in behind in that melee was in trouble. Franny is the same at any track in the country - he brims with confidence. He never worries about the opposition or other jockeys.
"He believes he is good as anybody and he comes into his own on a difficult track like Chester."
He added on the winner: "We ran him in the Cesarewitch and it was far from clear cut whether he stayed or not. I still had doubts today, particularly in this ground.
"Franny got second pick, but that was before he knew what the ground was and I think he might have switched to Lucky Deal given the chance late on. He jumped and took the race right from the beginning.
"It is great we have some good handicappers, particularly in this (staying) division. We will see what the the handicapper does, but the Northumberland Plate and Cesarewitch at the end of the year would be for him."
Alan King, trainer of Who Dares Wins, who was third 12 months ago, said: "I'm delighted with that. He always does that and hits a flat spot, whether it is quick ground or slow ground and he stayed on really well - it is very reminiscent of last year really.
"The winner bolted up, so I have no qualms about that, I'm just delighted we have got second.
"He will have an entry at Royal Ascot and if it was soft ground he would go for the Queen Alexandra, otherwise he will be in the Northumberland Plate. It will be one or other, I suppose."