Only a nerd would spend 10 years filling a binder with trial-and-error recipes trying to create the ideal spice rub, says Jennifer Wood, referring (lovingly) to her husband Brad Perriello. He tracked every tweak. Finally Perriello had a winner. Wood took it upon herself to package the blend in a tin can and market it as Herd Nerd SPICE, a fragrant mix of smoked paprika, brown sugar, chile powders, cumin, and granulated garlic and onion. It turns out the rub has become popular and sold in dozens of stores. Later, Wood came up with the idea of raising the rub’s fieriness and produced Herd Nerd HOT. Now, a new addition to the line is Herd Nerd SALT, which combines smoked paprika, chili powders, and cumin with kosher salt. Mildly spicy with a subtle smokiness, the seasoned salt is for sprinkling on chicken, fish, omelets, into soups or on popcorn — or whatever else you want to put it on ($12.99 for 3 ounces). Use it in place of table salt when you wish to add nuance and raise the flavor level of a dish, or to coat the rim of a Bloody Mary glass. Herd Nerd SALT is available at Pemberton Farms Marketplace, 2225 Mass. Ave., Cambridge, 617-491-2244; Arlington Centered, 487 Mass. Ave., Arlington, 781-643-6700; Davis Squared, 409 Highland Ave., Somerville, 617-666-6700; Volante Farms, 292 Forest St., Needham, 781-444-2351, or go to www.herdnerdspice.com.