In my big ole mash pot I threw in 12cups of rolled barley, 12 cups of rolled corn, 12 cups of barley chop. (sorry I usually go by weight but someone borrowed my scale so I winged it) Then I dumped about 30 litres boiling hot backset (from the barley whiskey I just finished distilling)
Stirred it up well and covered the pot.
When the temp of the mash got down to 66.5 deg C. (striking temperature) I added 8 or 10 cups or so of ground malt stirred it in, put the lid on and left it sit till morning.
In the morning I dumped it into my fermenter, added about 5 kg or so of sugar, topped the mash off with water to bring it up to about the 50ltr mark on my fermenter and added my yeast. (My yeast is a culture that I've kept alive for a few generations of mash now.)
After a couple hours it was bubbling away happily. This weekend it is still working. It has a grain crust on top and it is rolling steady. Next weekend it should be good to go.
I have no idea what it will be like...maybe it will taste like poo... I used a lot of backset. We'll soon find out

I like to try to be efficient, thats why I tried this method...rather than using more time and energy to cook a mash. Time will tell if this method is a good thing or not.