In the movie “Willy Wonka and the Chocolate Factory,” Mr. Wonka, wearing a long velvet jacket and a top hat, leads Charlie on a tour of the colorful factory, which features a chocolate river, hot chocolate trees and a chocolate waterfall that flows down jagged rocks. Nowhere in Wonka’s big, bright factory is there a washing machine.

“This is easily the smallest chocolate factory in the world,” said Ben Rasmussen, standing in his laundry room, where he makes 40 pounds (that’s about 360 bars) of chocolate a week.

Rasmussen started Potomac Chocolate 31/2 years ago in his house. He sells his chocolate bars to 75 stores in the United States, including about 10 in the Washington area, and a few in Canada and Europe.

“I fell in love with chocolate,” he said.

Where the love began

For Rasmussen, who is 38, chocolate love started only recently. While growing up in Woodbridge, Virginia, Rasmussen liked Three Musketeers bars. He didn’t like dark chocolate, which is what he makes today.

All that changed one night five years ago, when his brother brought him some gourmet chocolate.

“It’s this moment when you’re like, ‘Holy cow! I had no idea chocolate could taste this way,’ ” he said. “It is something completely different than anything I’ve ever experienced.”

Rasmussen became obsessed with chocolate and started learning about it, trying different kinds and hosting chocolate tastings for his friends and family. Even his youngest daughter, who was 3 years old at the time, began talking about the taste of the chocolates.

Good chocolate, Rasmussen discovered, can hint at many flavors, such as nut, orange and cinnamon.

“We all grow up thinking chocolate is chocolaty, but it has so many different flavor notes,” he said.

What is dark chocolate?

Cacao (sounds like ka-COW) beans are the main ingredient in Rasmussen’s chocolate. They come from cacao trees, which grow in warm temperatures in places such as South America. The seeds grow in brightly colored pods the size of footballs, with about 50 seeds in each pod.

Differences in soil and weather affect the taste of the chocolate that a tree helps produce. Labels on gourmet chocolate bars often state where the beans came from and how much cacao bean is in the chocolate. (Rasmussen’s favorite bars are his 70 percent Upala bar and his 70 percent San Martin bar. Upala is a city in Costa Rica and San Martin is a region in Peru.)

After the seeds are pulled out of the pod, they are left to dry for about a week, during which time they start to brown and take on their chocolaty taste. At that point they are no longer seeds, because they can’t grow, so they’re called beans.

“My passion is bringing out the flavor of the bean,” Rasmussen said. “There are these great flavors of the bean. How can I bring that out as much as possible?”

Making the chocolate

The ingredients in good dark chocolate may be simple, but making it is anything but. As much as 450 pounds of beans — that’s more than twice the weight of an average-size man — arrive on Rasmussen’s doorstep every few months. Rasmussen sorts the beans by hand, discarding any sticks, leaves and broken or clumped beans. Then he roasts the beans in a rotating metal cylinder in an oven that he has adapted for making chocolate. He lets the beans cool.

Next, he puts the beans in a winnower, a machine that he made out of a juicer, a vacuum, some plastic piping and a metal funnel, which removes the husk (or shell) of the bean. What remains is called the nib.

“Most of my stuff is DIY,” or do it yourself, he said. The equipment otherwise would be too expensive.

Rasmussen puts the nibs in a melanger (meh-lon-DJAY), a French word that means “to mix.” The big pot spins fast. He lets it spin for days so the nibs become liquid. He adds sugar. This mixture — now it looks and tastes like chocolate — goes into a second spinning machine that heats, cools and heats it again. This process, called tempering, gives the chocolate its shine and snap. The chocolate goes into plastic bar molds and is refrigerated. Lastly, Rasmussen wraps the bars in plastic and paper.

Making chocolate is a lot of work, but it isn’t even Rasmussen’s full-time job. He works as a computer manager. (He also has four kids.)

“I found something I love to do,” he said. “It’s all about putting in the time and effort.”

The future

Every year, Rasmussen has sold more chocolate than the year before. Its popularity has grown through word of mouth, which means that people tell other people about his chocolate. He’s thinking about expanding his work space by adding on to his house. For now, he said, it works okay for a one-man chocolate factory.

With chocolate, “you can go as deep as you want with the creative side, the scientific side, the technological side,” he said. “There’s so much room for learning new things and improving. I think my chocolate is awesome, but there’s a lot of room for improvement, and that’s what I’m trying to do.”

Taste chocolate like a professional

Here are some tips from Potomac Chocolate’s Ben Rasmussen.

1. Slow down! Chocolate should not be a “sugar delivery mechanism,” Rasmussen said. Eating it is meant to be a calm and yummy experience.

2. Look at the chocolate. It should be the same shiny, dark, smooth color throughout the bar. If there is a lighter color in spots — that’s called chocolate bloom — it means the chocolate is not perfect.

3. Smell the chocolate. Does it smell like chocolate to you?

4. Break off a small piece of the chocolate. Good dark chocolate will snap when you break it.

5. Take a sip of water to clean your mouth. Place the piece of chocolate on your tongue and let it melt. What hints of flavors do you taste? Orange? Nuts? Caramel? Raisins? Is it intense? Do you like it? Does the taste change as the chocolate melts in your month? Does the chocolate feel creamy or chunky on your tongue? As you enjoy, think about it.

See the chocolate-making process for yourself

Is your mouth watering for chocolate? It is almost Valentine’s Day, after all! If you’re curious about how chocolate is made, tour a local chocolate factory.

What: Spagnvola Chocolatier factory tour.

Where: 360 Main Street, Gaithersburg, Md.

When: Every 15 minutes, from 2 to 5:45 p.m. Saturdays and Sundays.

How much: Free.

For more information: A parent can reserve a spot by visiting the Web site,, or by calling

— Moira E. McLaughlin