The Bees scored three times in 15 first-half minutes and went on to net four against the Foxes for a second time this season, following the 4-1 home victory in November.
It meant a 10th Premier League defeat for Ruud Van Nistelrooy in his short spell in charge of Leicester.
The hosts started the better of the two teams but imploded in the space of 15 first-half minutes. Goals from Yoane Wissa, Bryan Mbeumo and captain Christian Norgaard had fans streaming for the exit doors before the half-time whistle.
Brentford had further opportunities to increase their lead most notably through Mikkel Damsgaard but Thomas Frank’s side finally had a fourth when Fabio Carvalho slotted in his second of the season to seal a fourth successive win…