A quick review of the specifications we proposed will provide your first clue:
Color = 30+ SRM
Original gravity = 1.0601.080
Final gravity = 1.0101.016
Bitterness = 5090 IBU
Alcohol by volume = 6.08.5%
Your second clue is a list of the proposed style descriptors:
Aroma Prominent Northwest variety hop aromas resinous pine, citrus, sweet malt, hints of roast malt, chocolate and/or Carafa®, can include mild coffee notes, dry hopped character is often present.
Appearance Deep brown to black with ruby highlights. Head varies from white to tan/khaki.
Flavor A balance between citrus like and spicy Northwest hop flavor, bitterness, caramel and roast, chocolate, or Carafa® type malts. Any roast character should be subdued. Black malt is acceptable at low levels but should not be astringent. Any burnt character is not appropriate. The finish should be dry with caramel malt as a secondary flavor. Diacetyl should not be present. The main emphasis should be on hop flavor.
Mouthfeel Light to medium, hop bitterness and tannins from roast malts combine to create a dry mouthfeel. Resinous character from high levels of dry hopping may create a tongue coating sensation.
Comments Some brewers prefer to cold steep the dark grains to achieve a very dark beer without the tannin contribution of adding these grains to the mash. The use of Sinamar® color extract to enhance the color is common.
What differentiates Cascadian dark ale from a hoppy porter or stout? There are really three main differences. The first would be the basic hop profile. These beers are brewed using traditional IPA bittering, flavor and aroma hops with citrus, spice and floral characteristics. Typical hop selections would be Columbus, Centennial, Chinook, Amarillo, Simcoe and Cascade or hybrids of these like Warrior or Magnum. The second would be the vastly reduced roast malt flavor contributions. The use of debittered Carafa® malts instead of black patent or roast barley. This provides color without the harsher, burnt flavor profiles of robust porters or stouts. And finally, the third is the much drier finish. This is achieved through the use of very little light caramel malts and highly attenuative yeasts.