Spent Hop ESB

(5 gallons/19 L, all-grain)
OG = 1.048  FG = 1.010
IBU = 22  SRM = 5  ABV = 5%

Ingredients

9.5 lbs. (4.3 kg) Crisp Maris Otter pale malt
5 oz. (135 g) acidulated malt
3 g gypsum
18 oz. (0.5 kg) spent fresh Cascade hops (first wort hop)
16 oz. (0.45 kg) spent fresh Cascade hops (whirlpool)
½ tsp. Irish moss
½ tsp. yeast nutrient
LalBrew Nottingham yeast 

Step by step

Mash in Maris Otter malt at 150 °F (66 °C) with roughly 3.25 gallons (12.3 L) of water. Add gypsum, take a mash pH reading and adjust if needed to 5.3. Rest mash for 1 hour, recirculate/vorlauf for 30 minutes or until wort is clear, sparge with 4 gallons (15 L) of 172 °F (78 °C) water, then lauter to target a preboil volume of 6.5 gallons (26.5 L). Add 18 oz. (0.5 kg) first wort hops to kettle in bags, then boil for 60 minutes. At 15 minutes, add the Irish moss and yeast nutrient. Add 16 oz. (0.45 kg) spent fresh wet hop cones to the clean mash tun, and at the end of the boil transfer the wort to the mash tun to rest for 30 minutes. Stir occasionally.

I like using English ale strains, however feel free to use your favorite IPA strain. Ferment at the suggested yeast strain temperature. Ferment until final gravity has been reached, usually within 7 days, and do a diacetyl rest. Cold crash and package at 2.65 volumes CO₂.

Extract Version: 
Replace the grains and gypsum with 6.6 lbs. (3 kg) Maris Otter liquid malt extract. Bring 6 gallons (23 L) of water to a boil and turn off heat. Stir in the malt extract, return to a boil, and follow the remainder of the all-grain recipe.