This can be attained on the first act of Press Garden Zone. But before starting, whilst in the Mania Mode screen press Y to bring up the Game Options and enable Debug Mode.
If you haven't unlocked this Zone, to access the Level Select Screen, highlight the save file and hold X followed by holding Start.
When the Zone loads up, transform into a Ring by pressing X and follow the route shown in the video to the area with a large amount of wooden crates (there is also a Flame Shield Monitor here). Press A to scroll through the items available until you reach the Starpost. Place it on the level by pressing Y and scroll through again with A until you find the Large Ring and place a few down. Turn back into Sonic by pressing X and collect the Rings and enter the Special Stage via the Starpost. Complete the Special Stage (by hitting a Red Sphere) and return to the level.
To unlock the achievement break the Flame Shield Monitor and destroy all the wooden crates found here (there is also a 1-UP Monitor hidden underneath).