The visitors opened the scoring with a strike from George Bissett after only seven minutes and were 2-0 up three minutes later when Nathan Kamara hit the target.
Prolific marksman Danny Gray then netted a brace to make it 4-0 at the break.
Dunnington improved in the second hald, scoring the only goal when Josh Martin hit the back of the net.
Wiggington Grasshoppers lost ground in the title race when they went down 3-2 at Hounds.
The hosts went ahead with an early Chris Jackson penalty, but Grasshoppers fought back with a splendid 20-yard strike from Tom Jackson that left the Hounds ’keeper with no chance.
The away side then took the lead just before half-time with a deft lob from Lee McQuade, only for a free-kick from Ryan Whitlam to level in stoppage time.
With 15 minutes remaining, Hounds were awarded a second penalty and again Chris Jackson made no mistake from the spot.
New division two leaders York Nomads ran out 8-4 winners at Marcia Grey, led by a hat-trick from John Cavanagh and further goals from Chris Bilton (2), Nick Lawrie (2) and Liam Wingfield.
The home side’s replies were shared by Steve Pickup (2), Alex Day and Chris Murcutt.
Haxby Lions climbed out of the relegation places after beating basement side Hemingbrough United 3-2.
On target for Lions were Mark Christie, Paul Scaife and Tom Beattie with a penalty.
Tom Collins and Luke Zacharenko replied.
Beeswing upset the form-book by beating Leeman United 4-3 with plunder bagged by Myron Turbine (2), Mark Triffitt and Rich Burnitt, the latter after a 50-yard solo run.
Britannia Tadcaster are the new leaders in division four after hammering Selby Railway 10-2, while Jonathon Lunt scored Eggborough Rangers’ only goal in their 3-1 defeat by F3.
Triple slam to no avail
NICK Hutchinson hit the target three times for Severus in their Ian’s Cars of Barlby League Cup third round tie against derby rivals Acomb Celtic.
But the triple feat proved to be all in vain as Hutchinson finished on the losing side.
Celtic hit back with goals from Kevin Scott, Lee Powell, Neil Richardson and Cameron Sanderson to win the tie 4-3.
Derwent United are through to the next round after beating NUR 5-0.
On target were Kingsley Daffern (2), Marcus Godsall, Simon Cooke and Dean Nuttall.