Evans delivered an impressive display to overcome extreme wet conditions, and even snow showers, to lead home eight-time world champion Sebastien Ogier by 1m17.7s.
Toyota completed an utter domination of the 22-stage asphalt event, with two-time world champion Kalle Rovanpera completing the podium, 1m46.5s adrift.
Evans set four fastest times across the four-day event, but it was his stunning display on Friday in horrendous wet conditions, that provided the platform for victory.
The Welshman started Friday in ninth after Thursday's Toyota Stadium super special but leapt into a 26.0s lead by the end of stage two following a brave performance on saturated roads that were made even more slippery by leaves and pine needles.
A lack of visibility caused by misted-up windscreens that affected all Rally1 cars only added to the challenge.
Organisers cancelled stage four such were the severity of the conditions.
Hyundai's Thierry Neuville emerged as Evans' nearest rival. The Belgian closed within 10.5s before running off the road at the first corner of stage six which ended his hopes. Neuville rejoined the rally on Saturday and claimed the full bonus Power Stage points.
Neuville's demise handed Evans a 44.4s lead over Ogier which ballooned to 1m49.9s by the end of the day. Ogier received a one-minute penalty after leaving service six minutes late following a repair to his GR Yaris' chassis, caused by contact with a barrier on stage five.
Evans was kept on his toes by the changeable weather conditions as snow briefly arrived on Saturday afternoon, but the Toyota driver remained in control throughout to seal victory from Ogier. The result clinched the runner-up spot in the championship for Evans.
Rovanpera's victory charge was dented on Friday after losing 1m36.4s after only three stages. The Finn, troubled by a foggy windscreen, faced the worst of the conditions which he declared the most difficult of the season.
Rovanpera was unable to recover the time loss and ultimately settled for third ahead of the sole remaining Hyundai driven by Esapekka Lappi (+2m50.3s).
Lappi struggled for confidence behind the wheel of his i20N for the majority of the event finding himself in seventh at the end of Friday. The Finn steadily improved to climb to fourth before coming under pressure from Toyota's Takamoto Katsuta across Sunday's stages, but Lappi held onto the spot.
Katsuta could have found himself in the fight for victory had he not found the trees on stage two, damaging his GR Yaris' radiator. The Japanese driver then produced a stunning fightback from ninth to fifth (+3m10.3s), scoring 10 stages wins in the process, more than any other driver.
M-Sport's Ott Tanak was another victim of a misted-up windscreen on Friday which cost him more than three minutes. The 2019 world champion rose back to fifth despite battling electrical issues on his Ford Puma.
Tanak ultimately slipped to sixth (+3m28.3s) at the finish in his final event for M-Sport before moving to Hyundai next year.
Hyundai's Dani Sordo and M-Sport's Adrien Fourmaux, the latter making his Rally1 return, crashed out at the same corner where Katsuta damaged his radiator on stage two, ending their rallies on the spot.
WRC2 champion Andreas Mikkelsen claimed a fourth class win finishing seventh overall. Mikkelsen had held fourth position heading into Saturday following an impressive performance on Friday. The top 10 was completed by Rally2 competitors Nikolay Gryazin, Kajetan Kajetanowicz and Rally4 driver Hiroki Arai.
