Paul brings an educator's background to his discussion of mesquite, which grows across the American Southwest as well as the Southern Hemisphere. "It's been an important plant to indigenous people as a source of food, a source of wood in bows, and fuel," he lists off.

Fittingly, Paul taught environmental education at a private school for several years before beginning a new -- and largely self-taught -- career. His company Arroyo Design earned a glowing reputation during its 30 years in business for making fine furniture out of mesquite wood, sometimes building pieces for notables like Linda Ronstadt, Gene Hackman, Paul and Linda McCartney, and the Dalai Lama. Despite mesquite being a difficult wood to work with compared with other types, Paul says, "It just turns into a really spectacular piece of furniture."

But Paul had never imagined using the region's velvet mesquite wood to smoke barley. That is, not until his wife pondered aloud -- over a meal of mesquite-grilled meat accompanied by Scotch -- if it would be possible to make a spectacular American version of a single malt whisky by using mesquite wood to smoke the barley, rather than the peat used by distillers in parts of Scotland. "I thought, what a great idea!" says Paul. "The notion of being able to create an American single malt whiskey that is from the place that I grew up -- and that I love -- just captivated me."

Today, connoisseurs find themselves captivated by the results as well. Two of the whiskeys have won double gold medals at the San Francisco World Spirits Competition. Furthermore, The Whiskey Advocate gave its mesquite-smoked selection Dorado a rating of 90, and the Wine Enthusiast even rated its unsmoked Classic whiskey 93 points. Comparing his own mesquite-smoked whiskey to a peat-smoked Scottish single malt, Paul notes how "mesquite is softer on the palate than peat -- and it doesn't give you those medicinal notes on the nose and the palate" that peat often lends. He also says his Dorado spirit displays "complexity" with flavor notes of leather and tobacco, a caramel sweetness, and sometimes even Ancho chiles in the mix.

The distillery business has become way more complex since Paul co-founded the company with his daughter, Amanda Catherine Paul. Amanda, he says, "helped me get all the permitting on all the three levels -- local, state, and federal." And she works on the brand's marketing. "She manages our whole aesthetic, making sure that we stay on-brand," says Paul.

Beginning with an alembic 40-gallon Portuguese still in 2011, Whiskey Del Bac began producing about 50 cases a year for the Tucson market. Today, it makes about 5,000 cases per year using its 500-gallon still, and the spirits are sold at outlets within 17 states. Online ordering allows consumers in additional states to obtain bottles, as well. For its smoked whiskeys -- its aged Dorado, its unaged Old Pueblo, and its seasonal Distiller's Cuts -- a single tank germinates 5,000 pounds of barley at a time, which next gets smoked within the very same vessel, prior to being used to brew the mash.

"I had been telling my board that the business had grown in complexity -- kind of beyond my industry knowledge and also beyond my managerial abilities," says Paul, who now serves as the president of the board of directors of the company that makes Whiskey Del Bac, Hamilton Distillers Group. Two years ago, Kent Cheeseman, who previously held the title of manager of operations at Utah's High West Distillery, was appointed the company's CEO. "Kent has put together a fantastic team," enthuses Paul. That team has included, since 2021, Head Distiller Mark A. Vierthaler, who previously worked at Maryland's Tenth Ward Distilling Co. "He has much more knowledge than I ever had about distilling," says Paul of Vierthaler. "He's adventurous, he's curious, he makes things happen."

Not all of Paul's early experiments as a self-taught distiller panned out. At one time, he tried aging his whiskey in a charred barrel made out of mesquite wood, instead of the oak upon which the company ultimately settled. "It tasted horrible," laughs Paul.

But Paul loves how the name of his whiskey brand rolls off his tongue -- even though people outside the Southwest sometimes find Whiskey Del Bac, instead of being written out as Del Bac Whiskey, to be quirky-sounding or confusing to them. The whiskey takes its name from Tucson's eighteenth-century Mission San Xavier del Bac, and Paul notes how "whiskey" is an English word, while "del" is Spanish, and "bac" is native Tohono O’odham. Strung together, "Whiskey Del Bac" means, according to Paul, "whiskey from the place where the river reappears in the sand."

"I've always loved living in a border region, because it makes you look at the world in different ways," says Paul about Tucson, where whiskey matures faster in the barrel because of the sometimes-drastic temperature shifts within a single day that move the whiskey in and out of the wood. "And the blending of cultures is so enriching -- and so much fun."

Challenges: "Marketing is a huge challenge," says Paul, who describes himself as having once been "super-naïve" about that aspect of the business. "I just thought we'd make a great single malt whiskey, and the world would beat down our door. Doesn't happen," he continues. "You've got to get out there and really sell it." The company plans to invest additional money into sales and marketing, he notes.

Opportunities: "Elevating the public's awareness of what an American single [malt] whiskey is," says Paul. To assist in that effort, along with other distillers, Paul recently joined the board of the American Single Malt Whiskey Commission. The group has been working on getting official recognition for the style, just like bourbon has become legally codified. And it seems to have made progress on that front: "The TTB accepted our vocabulary, our wording for the standards," says Paul about how the whiskey will need to be, for example, made from a 100 percent malted barley recipe by a single distillery.

Paul is also on a personal quest to popularize the term "mesquited," in order to signify something similar to what "peated" means in terms of peat-smoked whisky in Scotland.

Needs: "Cash," he says. "We're always putting cash back into the business."