Flavio Paixao netted a consolation for Accies as the Hibs onslaught eventually subsided, but both teams had a succession of chances to add to the scoreline in what was one of the most open games of the season.
Hibs had not scored five times in a game since putting Kilmarnock to the sword at Hampden Park in the League Cup final almost three years ago.
Each side made two changes, Hibs recalling Nish and handing fit-again Kevin McBride his first start for more than two months, while Hamilton drafted in defenders Mark McLaughlin and Richie Hastings for what was their fifth game in a fortnight.
Accies were without a win since mid-December in all competitions but were not short of confidence after three strong performances against Rangers in league and cup this month.
They started as such and were denied a sixth-minute opener by McBride's clearance after McLaughlin hooked the ball goalward following a corner.
Hibs clicked into gear and a wonderful stop from the in-form Tomas Cerny kept out Stokes' low finish before Riordan saw a goal ruled out for offside after tapping in David Wotherspoon's cross-cum-shot.
It did not matter as a lovely move put the home side in front three minutes later, sh clipping the ball over Cerny after a great run and pass from Liam Miller.
Only a brilliant reflex save from Graeme Smith prevented Hamilton levelling, the keeper somehow pushing Mickael Antoine-Curier's close-range finish wide.
They were made to pay when Stokes scored a controversial second for Hibs, barging Alex Neil off the ball before firing a deflected finish past Cerny.
Hastings' looping cross then hit the top of Smith's crossbar and Nish failed to capitalise after being put through by a misplaced Accies pass.
Simon Mensing, who had seen an earlier effort tipped over, curled a 20-yard shot wide but it was 3-0 on the half-hour when Riordan found the empty net after Stokes' finish was pushed onto the bar by Cerny.
John Rankin's audacious lob sailed over the top and there was a brief respite in what had been a frantic first half before Smith got down well to deny Antoine-Curier for a second time.
Cerny was called into action again less than three minutes after the restart, springing to his right to palm a Stokes free-kick behind.
But he was helpless to prevent Riordan netting from the other side of the box moments later after Neil was booked for hauling John Rankin to the floor.
The keeper did keep out the striker's next effort before Smith followed suit at the other end from Marco Paixao.
Hibs immediately broke downfield and Stokes was given all the time and space he needed to fire his second beyond Cerny.
Hamilton withdrew Neil for Kyle Wilkie on the hour mark as the home fans revelled in their team's goal glut.
Abdessalam Benjelloun replaced Nish as Hibs boss Hughes turned his attention to Wednesday's trip to Celtic.
Liam Miller followed for Patrick Cregg in the 70th minute, while Accies threw on David van Zanten and Stuart Elliott for Trent McClenahan and Marco Paixao.
Twin brother Flavio immediately pulled a goal back when he converted Elliott's cross at the far post.
The final change saw Danny Galbraith introduced for McBride before Rankin was yellow carded for a challenge that left Wilkie needing treatment.
Accies looked like finishing the stronger, James McArthur seeing two efforts saved by Smith, while Mensing blasted wide from close range.
But Stokes twice went close to completing a hat-trick late on, missing Galbraith's cross before shooting over Cerny's bar.
McLaughlin's stoppage-time booking completed Hamilton's misery.