Although it's not a kit, this is my favorite extract recipe. I have an AG version too if someone wants it.
River Thames ESB
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Brewer: dysphoria
Style: Extra Special/Strong Bitter (English Pale Ale)
Batch: 5.00 gal - Extract
Characteristics
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Recipe Gravity: 1.055 OG
Recipe Bitterness: 47 IBU
Recipe Color: 11° SRM
Estimated FG: 1.014
Alcohol by Volume: 5.3%
Alcohol by Weight: 4.2%
Ingredients
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Pale liquid malt extract 7.00 lb, Extract, Extract
Crystal 60L 0.50 lb, Grain, Steeped
Torrified wheat 0.50 lb, Adjunct, Steeped
First Gold 6.5% 1.50 oz, Pellet, 60 minutes
Kent Golding 5.1% 1.00 oz, Whole, 10 minutes
First Gold 6.5% 0.50 oz, Pellet, 5 minutes
Kent Golding 5.1% 1.00 oz, Whole, 0 minutes
London ESB Ale yeast 2.00 smack packs, Yeast,
OR
Safale S-04 11.5g Packet, Yeast,
Notes
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Boil three gallons of water, cool and transfer to sanitized container(for top-up in fermenter).
Add 3 gallons of water to kettle, heat to 160F.
Add Crystal 60L and Torrified weat to grain bag and steep in kettle for 30 minutes(feel free to agitate the grain a bit to make sure it's evenly wetted).
After 30 mintues give the grain bag a couple good dunks and remove. Allow to drain thoroughly(squeeze it if you fancy).
Bring to a boil, add malt extract slowly - stir well to prevent scorching(I generally add the LME right before it comes to a boil).
Follow hop schedule as shown above.
Add 1 whirlfloc tablet (or a hearty pinch of Irish Moss) at 10 minutes left to boil.
At flameout, add final hop addition, stir, Chill.
Once wort has reached pitching temp, move to fermenter and top-up to 5 gallons with pre-boiled water from sanitized container.
Aerate well and pitch yeast.
*Note - Due to my experience with Wyeast London ESB under attenuation, I tend to either pitch two smack packs or use a starter.
If dry yeast is preferred, I have had excellent luck with a single 11.5g Safale s-04 packet.
(However, it should be mentioned for the newer brewer that this yeast can have some serious vigor. Ready the blow-off tube.)