The match got off to a strange start with Vitinha kicking the ball off the pitch on purpose, but a sense of familiarity soon returned with the midfielder getting plenty of touches.
The Portugal international then played a vital pass to open up the Nerazzurri just 12 minutes into proceedings, finding Doué who selflessly squared the ball for Achraf Hakimi to convert against his former club.
Having been the provider for the first, Doué scored PSG’s second just eight minutes later, as he controlled Ousmane Dembélé's pass and hit a strike that deflected in off Federico Dimarco, who had dropped behind his fellow defenders.
Even though the Nerazzurri were largely suffocated by Les Parisiens and had to resort to going long, they did have chances from corners that Francesco Acerbi and Marcus Thuram couldn’t capitalise on, as they sent their respective headers off-target.
There were also scares before the break with Dembélé ghosting behind Dimarco but being unable to turn home a cross from Doué, who then struck marginally wide, while Khvicha Kvaratskhelia had a shot deflected behind before heading onto the roof of the net from the ensuing corner.
Kvaratskhelia had two more opportunities within five minutes of the restart without hitting the target, and Dembélé also sent his attempt wide.
Simone Inzaghi responded with a double change in the 54th minute, and Nicola Zalewski showed intent but saw his shot blocked and then got the game’s first booking within two minutes of his introduction.
Inzaghi then received a booking himself for showing his frustrations, almost summarising Inter’s night so far.
But things soon got even worse for Inter, when Yann Bisseck was forced off through injury shortly after being brought on. And before the German had even reached the bench, Doué applied a first-time finish to Vitinha’s pass that left Sommer helpless.
Lautaro Martínez and Thuram got in each other’s way when there was a chance to restore a slither of hope for Inter, who were left in complete despair again as Dembélé slipped through Kvaratskhelia and he applied a composed finish, becoming the first-ever Georgian to net in a UCL final.
PSG were now targeting the first five-goal winning margin in a UCL final, and they got it four minutes from time, when PSG-bred teen sensation Senny Mayulu played a one-two with Barcola and smashed the ball in off the post.
That put the top hat on a night that saw PSG become the first French side to lift the UCL since 1993, when Marseille were crowned its inaugural winners. In doing so, they also completed their first-ever quadruple.
In contrast, a campaign that had promised so much for Inter ended without a single piece of silverware, after their second UCL final defeat in three years.
Flashscore Man of the Match: Désiré Doué (Paris Saint-Germain)