Formica volleyed home a Morten Gamst Pedersen cross on 40 minutes and four minutes after the break in Saturday's Premier League clash at Ewood Park, Hoilett let fly with a 25-yard screamer into the top corner.
Their goals brought an emphatic end to a run of five consecutive league defeats which had plunged beleaguered Steve Kean's men back into the drop zone.
Kean had made two changes for the crunch encounter, bringing back Formica as well as Gael Givet, whom the manager had declared "not in the right frame of mind" prior to last week's loss at Swansea.
All week Kean had insisted his side's fighting spirit was undamaged, and it was a mark of their belief that they managed to ride out the difficult early pressure.
Paul Lambert's Canaries looked flat-footed after last week's mauling by Manchester City and contributed little as Rovers took control from the start.
Bradley Orr and Scott Dann came close in the early stages but the tension was evident in boisterous calls for Kean's dismissal, which began before 10 minutes were on the clock.
James Vaughan had a half-chance for the visitors as the Rovers defence panicked in their own box, but at the other end Ryan Bennett had to hook clear to deny Hoilett.
Jonathan Howson came close for Norwich on the half-hour when his powerful long-range drive was tipped over by Paul Robinson in the Rovers goal.
But it was Rovers who managed to retain the upper hand, Yakubu almost connecting with a dangerous cross from Pedersen in front of goal.
And the Nigerian had his side's best early chance in the 37th minute when Pedersen headed down and he attempted an overhead kick which struck the base of the post.
Three minutes later Rovers grabbed the lead when Yakubu fed Pedersen on the right and the recalled Formica met the Norwegian's cross with a crisp sliding volley past Ruddy.
Rovers doubled their advantage shortly after the restart with Hoilett's seventh and best goal of the season, cutting in from the left flank and letting fly past a helpless Ruddy.
The Canaries were offering precious little in response as Rovers began to take a hold on the game, Hoilett almost finding Yakubu in front of goal on 55 minutes.
The visitors did briefly rally in the final quarter, Elliott Bennett's cross just eluding Elliott Ward, then Aaron Wilbraham bringing a fine low save out of Robinson.
But Rovers seldom looked troubled by the Norwich revival, and came close to a third 10 minutes from time when substitute Anthony Modeste headed inches over from another Pedersen cross.