After learning all about the types of bitters on the market and the history of the non-potable tincture last week with Bill and Lill Buitenhuys of AZ Bitters Lab, Travis Nass of the Last Drop Bar at the Hermosa Inn shows us this week how to use bitters in a cocktail. Nass says that if you're using bitters properly, it should "season" the cocktail, without your actually being able to tell there are bitters in it at all. However, you also can do what the bartenders do and take a full shot of Angostura -- though that can get expensive.

See Also: Bitters 101 with Bill and Lill Buitenhuys of AZ Bitters Lab

Call it peer pressure, but when Travis Nass poured a shot of straight Angostura bitters, we called his bluff, and let's just say, the iconic bitters brand is classified as non-potable for a reason. In any case, it is one of three bitters, Nass says, that should be the base of any bitters collection, along with Peychaud's and an orange bitters. He explains that these three will be the basis for about 95 percent of all classic cocktail recipes.

Aromatic bitters like Angostura and Peychaud's often don't add one specific flavor element to a cocktail, though Nass notes that they have ginger and anise qualities, respectively. Since this type of bitters is made with a robust blend of different herbal elements, their job is to add complexity to a cocktail, without any one flavor being dominant.

If you're looking for specific flavor elements, the flavored varieties can add peach, cinnamon, celery, and even chocolate notes, depending on which kind you buy. Nass says there are no hard-and-fast rules when using bitters, but he says aromatic and "baking spice"-flavored bitters tend to blend nicely with brown spirits.

If you like white spirits, orange and other citrus and fruity bitters are the way to go in most cases. You won't be able to pick out the bitters' notes, and the cocktail exemplifies their ability to magnify flavor elements in just a spirit alone.

"The job of bitters is to add flavor and not too much volume," Nass says. "Five or six drops makes all of the difference."

He says there are few cocktails that can't be improved with bitters. (He's even used bitters to made ice cream, and it turned out amazing, he says.) While he's seen very few misuses of it, he says more often than not if a cocktail seems to be missing something, it's bitters.

"Without bitters, I've tasted cocktails that have just turned out mediocre and flat," he says.

Nass demonstrates this in an experiment. He takes a mix of stirred rye whiskey and sweet vermouth. After tasting that, he adds bitters in the mix. After that, he does an absinthe mist rinse on the glass. Finally, he adds an expressed orange peel. Comparing the first to fourth iteration of an improved Manhattan you can see how much the little things really impact the flavor of a cocktail.

Finally, he mixes up an Old Fashioned, which had to have been one of the best we've tasted. Using a historic rye spirit, Turbinado sugar, and, of course, bitters, Nass explains that an Old Fashioned cocktail simply means spirit, sugar, water, and bitters. What you pick from there is all a matter of taste and what you have in your liquor cabinet.

Of his favorites, Nass picks out Bitterman's Elemakule Tiki bitters, a blend of cinnamon, allspice, ginger, and almond, as well as his blend of Don's bitters, which mixes absinthe and Angostura in the traditional Don the Beachcomber style. However, before there were tons of bitters available on the market, Nass usually just made his own varieties. He still makes some specialized blends, such as his Pho bitters which use the same herbal elements as the Vietnamese soup's broth, but can now concentrate more on making cocktails taste great, rather than just making every element of a cocktail.

When it comes to choosing which bitters you'll use, you can go by old cocktail recipes or even color, with Angostura adding a rusty red and Peychaud's adding a bright red, while many others are brown. Nass uses the Flavor Bible to pair flavors, but he says you can also smell your cocktail and then your bitters to try to see if the flavors mesh. In the end, with all of the bitters on the market, it's really about testing combinations for yourself.

"It's all about experimentation," Nass says. "You'll start to get a feel for it when you play around with bitters enough."

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