I wouldn't be exact...but starting with a blend of marris otter and standard british pale ale (maybe 60/40) as your base....then coming in with 5% aromatic, 1-2% special b, and 1% (or less) of a really high lovi roasted barley or even chocolate malt....mash the base malt seperatey at 156-158, while it mashes, make a tea with your fully converted malts, and add this directly to the kettle....then lauter out your first runnings into the kettle and really carmelize the thick wort, and cook it right down. Then boil the rest maybe 90 minutes and do a single hop addition of something clean and noble...ekg or nb aim for 25 ibus...add no hops inside 40 minutes and ferment 65 degrees with edinburgh ale yeast. I think the key here is carmelize your malts but don't extract tannins from roasted barley and special b in the mash, the other key is finish high, you need a high OG and a high mash temp...1.15 down to 1.028 or something like that