Real’s triumph ensured their coach Ancelotti collected his 14th piece of silverware across his two spells in charge of the club.
It also took the Spanish giants clear of AC Milan and Barcelona, who had won the trophy on five occasions.
The Italian’s task now will revolve around adding more honours and finding the most suitable system to get the best from the wealth of attacking talent at his disposal.
Bellingham occupied a much deeper role and was scarcely involved during the first 45 minutes, while Mbappe, Vinicius Jr and Rodrygo were starved of space and the ball.
However, after a tactical tweak at half-time saw Mbappe shifted left, the England midfielder came into the game and played a starring role thereafter.
He released Vinicius Jr for the opener and an incisive pass soon after put the Brazilian through on goal again, with goalkeeper Juan Musso coming to Atalanta’s rescue.
Given Real still have the likes of Eduardo Camavinga and David Alaba to return from injury, unused substitute Endrick waiting in the wings and many of their stars having trained together just five times before this performance, it will have sent out an ominous notice to their domestic and European rivals.