Source: Spencer Thomas (spencer@engin.umich.edu), HBD Issue #1819, August 31, 1995
Final result has medium-low carbonation and a complex malt-hops nose. The malty sweetness is balanced by the agressive hopping level, and high hop flavor.
You could probably pump up the gravity of this another 8-10 points (and thus the alcohol by another 1% or so) by adding a pound of sugar, with no deleterious flavor effects.
Take first runnings (drain all liquid from mash tun without adding any further sparge water(*)) to get about 4-4.5 gallons @ 1.080. Boiling down to 3 gallons will give an OG of 1.105 - 1.120.
Whirlpool, let settle for 15 minutes and siphon through counterflow chiller with aerating cane on end.
Pitch yeast slurry from a previous batch of Mild (probably YeastLab London Ale (it's a long story)). (By the way, this is my favorite way to pitch *enough* yeast for a barleywine.) Fermentation was active in 2 hours. Primary was about 2 months @ 65-70F, and dropped from 1.105 to 1.038.
Rack into secondary and add 1 oz of EKG plugs for dry hopping.
Bottle about 1 month later. Added new yeast, but no priming sugar.
(*) You can (I did) add more hot water to the remaining mash, and sparge out about 7 gallons more wort to make a Bitter at about 1.045.