my way -start with 32 litres water, add half a crushed campden tablet, stir well, leave 30 minutes, add AMS, leave 30 minutes , fit BIAB to FV,heat to 72 deg C, add 9 lb PM, 1.5 lb light crystal, .75 lb torrified wheat, heat to 68 deg C, insulate, wait for 1 hour, drain, boil 15 mins with no hops then add hops for 15,10,5 and 2mins, cool naturally for 2 hours then use water bath to cool to 21 deg C, pitch hydrated SO4 yeast to final 22 litre volume. Leave 5 to 7 days, then bottle. No idea what efficiency is. OG 11 brix and FG 5.6 brix. Start drinking after 7 days. Ice cubes in glass if ambient temp is above 15 deg c, or chill in fridge 2 hours (requires pre-planning and memory and legs)