The Brazilian finally broke the deadlock from 20 yards with a low, fizzing shot after the two sides had carved out numerous chances in a game where managers Marcelo Bielsa and Carlo Ancelotti met for the first time.
The visitors had been left frustrated after hitting the post through Jack Harrison in the first half and drawing fine saves from Jordan Pickford who could do little about the winner.
Leeds will point to their attacking approach – and keeping the league’s top scorer Dominic Calvert-Lewin in check – as key in their move up to 11th in the table.
Everton slipped to a fourth defeat in five games, making their unbeaten start to the season seem like a distant memory.
They carved out plenty of chances themselves, but could not beat Illan Meslier, who denied Richarlison, Allan, and Abdoulaye Doucoure.
The Toffees also showed their defensive frailties once more as Leeds picked them apart, which, but for better finishing, could have made the scoreline even more convincing for the visitors.
This is the first time boss Ancelotti has lost successive home fixtures since 2012 when he was a manager at Paris St-Germain.