Don't underestimate the power of the dark side, especially when you?re talking chocolate.

At Taza Chocolate in Somerville, Mass., near Boston, the bar has been set high, and the daily grind there involves a weighted Oaxacan stone that helps create the signature flavor and rough texture of the company?s chocolate.

?We're bringing a whole new meaning to Beantown,? says Alex Whitmore, co-founder of Taza, a reference to the imported, organic, and highly sought cocoa beans that are the building blocks for Taza's unique dark-chocolate discs.

?We make this very unique stone-ground, Mexican-style chocolate unlike anything you've probably ever had before. ... We're a bean-to-bar chocolate-making factory. We actually use raw agricultural ingredients, which is really unique.?

Taza, has opened their bean-to-bar process to visitors, with tours offered four days a week. From inception to confection, you get a chance to see how they make the products that are shipped all over the country (including to Whole Foods in Connecticut.) A retail store is part of the factory, and is open during the tours. The roasting, winnowing, grinding, tempering and wrapping is all done on premises.

Oh, and the sampling. Expect to try each of Taza's 11 exotic varieties, including coffee, salt and pepper, Guajillo chili and an antioxidant-bursting bar that 80 percent chocolate, which is as close to pitch black as there is in the chocolate-making world.

?It's a real artisan process to see it from bean to bar,? said Joel Barrera of Natick, Mass.

?It's really educational,? says Jamila Henderson of Boston, ?and we got to eat chocolate, so you can't argue with that.?

Taza Chocolate is at 561 Windsor St., in Somerville, Mass., near Inman and Union Square, and about 3 miles from downtown Boston. The hourlong tours are offered Thursday through Sunday and cost $5. For more information and a taste of their products, go to www.tazachocolate.com or call 617-284-2232.