HELP with a "Hong Kong Milk Tea Ale"

[BJBrewhaus]

I was gifted a copy of "Homebrew World" by Joshua M Bernstein. I thought I'd try a few recipes and came across an ambitious specialty ale recipe with tea. I need to figure out how much sparge water I'd need to make my target gravity. The tricky part is you add 2 gal of black tea to 3 gal of wort to bring it up to a 5gal batch.
Am I over thinking this? Is it just as simple as boiling until I get 3 gal of wort and risk added bitterness? Or should I under estimate my sparge water?

I brew on a Brewzilla gen 3.1.1 and have a little over a year experience with all grain and 20-some brews under my belt with the system and still learning. This recipe might be the most ambitious I've planned so any help is appreciated.

Here's the recipe per the book:

"Size - 5 gal
OG - 1.088 (1.077 before lactose)
FG - 1.010
IBU - 20
SRM - 23
ABV - 8.8%

Malts and Adjuncts:
9.6 lbs 2-Row Malt
1.92 lbs Maris Otter
0.95 lbs Biscuit Malt
0.95 lbs Flaked Oats
0.95 lbs Caramel Malt (80L)
0.42 lbs Roasted Barley
1.54 lbs Lactose
1 oz Nutmeg
2 gal Black Tea

Hops:
1 oz Fuggles (60 min)
1 oz Fuggles (30 min)

Yeast:
1 pack White Labs WLP002 English Ale

Notes:
Mash - Mas Temprature 66-67c, 60 - 70 mins

Brewing - Add Lactose with 15 minutes left in the boil. Add nutmeg with 5 minutes left in the boil. Collect wort until you have a 4 or 5 gallons. Boil down during 60 minutes to 3 gallons of finished wort. After the boil, add the tea to the top up to 5 gallons of finished beer.
For the tea, I use whole leaf Ceylon black tea and follow the instructions on the lable but cut about 20 percent of the brewing time off and steep at precise 100c. you want the tea taste with as few tannins as possible. I brew the tea the previous day in two 1-gallon carboys, then refrigerate them for 24 hours."

Recipe by Jordan Kostelac
Here's a link to the book if anyone's interested:
https://shorturl.at/hvwz8

[mumblecrunch]

Collect wort until you have 4 or 5 gallons. Boil down during 60 minutes to 3 gallons of finished wort. After the boil, add the tea to the top up to 5 gallons of finished beer. After the boil, add the tea to the top up to 5 gallons of finished beer.

There's your answer right there: "Boil down during 60 minutes to 3 gallons of finished wort."

In a normal 5 gallon batch you're probably boiling down more like 6 gallons to get 5 (or if you're like many of us, 6-7 to get 5-6 to account for later losses).

Assuming you've got software and it's dialed in for your system, including boil-off, the easiest thing to do is to plug the recipe into software and let it do the calculations. Set your batch size to 3 gallons into the fermenter, enter the grist using percentages if the software supports it or fractions of a kilogram if it doesn't, and then scale the recipe to the desired gravity.

[BJBrewhaus]

You're absolutely right and it's so painfully obvious now that you say this. I read the recipe 10 times and over thought it way too much but that is an incredibly simple solution! Thank you.