Astra stalling after stopping quickley?

I have an Astra 1600cc, year 2000. My car sometimes stalls when braking hard at traffic lights and roundabouts. It starts up, but will not rev or idle properly. About four or five minutes later, it starts fine.
The plugs are good, egr valve less than one year old. and coil pack fitted a month ago. Any ideas would be greatly appreciated.