For much more about brewing Belgian-style dark strong ales, see No Rests for the Wicked: Fit for a Chalice.
Batch size: 5 gallons (19 liters)
Brewhouse efficiency: 72%
9 lb (4.1 kg) extra light or pilsner dry malt extract (DME)
1.5 lb (680 g) Munich
8 oz (227 g) Belgian aromatic
7 oz (198 g) Special B
HOPS & ADDITIONS SCHEDULE
2 oz (57 g) Styrian Goldings at 60 minutes [17.5 IBUs]
1 oz (28 g) Styrian Goldings at 15 minutes [4.5 IBUs]
1 tsp (5 ml) yeast nutrient at 10 minutes
1 lb (454 g) Belgian Candi Syrup D-180 at 10 minutes
8 oz (227 g) turbinado sugar at 10 minutes
Wyeast 3787 Trappist High Gravity
Mill the grains and place them in a mesh grain bag. Steep in 1 gallon (3.8 liters) of 152°F (67°C) water for 30 minutes, then raise the temperature to 168°F (76°C). Remove the bag, rinse the grains, add 5 more gallons (19 liters) of water to your kettle, then bring to a boil. Turn off the heat and add the DME in batches, being careful not to scorch. Return the heat and achieve a rolling boil. Boil for 90 minutes, adding hops, yeast nutrient, and sugars according to the schedule. (Before adding the turbinado sugar, dissolve it in a bit of hot water or wort.) After the boil, chill the wort to 64°F (18°C), aerate thoroughly, and pitch plenty of healthy yeast. Ferment at 68°F (20°C) for 1 week, then raise the temperature to 72°F (22°C) until fermentation is complete. Crash and cold condition for several weeks. Rack to secondary and allow to settle before packaging in a keg or sturdy bottles, carbonating to at least 3.5 volumes. Cellar for weeks, months, or years.
I recommend pitching a four-liter starter or three packages of yeast. If your beer doesn’t seem to attenuate and tastes overly sweet, pitch an actively fermenting lager strain at its high kräusen—that should finish the job without altering the desired profile.