https://beerandbrewing.com/recipe-firestone-walker-merlin-milk-stout/
DIRECTIONS
Mill the grains and mash at 156°F (69°C) for 60 minutes. Vorlauf until the runnings are free of particles, then run off into the kettle. Sparge and top up as necessary to get about 6 gallons (23 liters) of wort—or more, depending on your evaporation rate. Boil for 90 minutes, adding hops and lactose according to the schedule. After the boil, chill to about 62°F (17°C), aerate well, and pitch the yeast. Ferment at 65°F (18°C), allowing the temperature to rise to 70°F (21°C) for a diacetyl rest when fermentation is nearly complete. Then crash, package, and carbonate to about 2.4 volumes of CO2.
BREWER’S NOTES
Take precautions against acetaldehyde and diacetyl—keep your sanitation regime airtight, aerate your wort thoroughly after chilling, pitch plenty of healthy yeast, keep the beer on the yeast trub only until fermentation is complete, and limit oxygen exposure after primary fermentation.
Hops: These are interchangeable; go for low-alpha, Noble-type varieties to get about 27 IBUs.