How to make the perfect cup of hot chocolate

Eight years ago, we approached coffee-obsessed Andrew Kopplin to walk us through the creation of a superior cup of hot chocolate. The recent polar vortex convinced us that it was time to revisit this important topic.

At his eponymous St. Paul coffee bar, the mornings are all about meticulously brewed lattés, macchiatos and cappuccinos. But as the day progresses, the clientele at Kopplin's Coffee (2038 Marshall Av., St. Paul, 651-698-0457, kopplinscoffee.com) tends to focus on the shop's meticulously prepared hot chocolate.

"In the afternoons, it's just about all we sell," Kopplin said. "That, and chai."

Unlike the shop's coffee beverages, which require the kinds of intricate equipment that few consumers keep in their kitchens, the hot chocolates on the Kopplin's menu — a semisweet version and a dark, bittersweet variation — are easily replicated at home. His affinity for hot chocolate began in 2006, as he was getting ready to open his coffeehouse.

"I'd been reading a lot about mochas," said Kopplin. "They were originally made with darker chocolate. I like dark chocolate, and mocha is how I got into coffee. It's my gateway drug. As I got into finer coffees, I got away from mochas, and realized that the reason why is because most mochas are so sweet. I mean, Hershey's syrup is the norm. So I wanted to make a mocha that a coffee lover would love. And of course, once you do that, you really have a great hot chocolate, once you take out the espresso."

Here's his quick course on the art and science of perfect hot chocolate.

Buy the best. Kopplin relies upon a 54 percent Callebaut semisweet chocolate, and an organic, 70 percent Valrhona dark chocolate. Both have an intense, rich flavor. "They're premium products without being ridiculously expensive," he said. "Nothing at Kopplin's is cheap, but in the end, you get what you pay for." (Callebaut and Valrhona products are available at Kitchen Window, 3001 Hennepin Av. S., Mpls., kitchenwindow.com and Cooks of Crocus Hill, three Twin Cities locations, cooksofcrocushill.com).

Break it up. At the shop, Kopplin pulses the chocolate in a food processor, "until it's basically a powder," he said. "But small pieces, or chips, will work just fine. The reason we chop it small is because we have to make the drink in less than a minute."

Don't forget this key ingredient. "The reason we add cocoa powder, and why we don't just chop up chocolate and put it in milk, is because cocoa powder helps the milk and the chocolate adhere to one another," he said. "You don't need cocoa powder if you heat up the milk and the chocolate super-slow, because then you can get the chocolate to incorporate. But it really doesn't want to attach to the milk molecules the way cocoa powder does. Chocolate has a richer taste, with unique, deep tones and complex flavor profiles, but cocoa powder makes hot chocolate feel thick, it has the mouthfeel." Kopplin invests in Valrhona cocoa powder. "I don't know enough about chocolate to say why it's better," he said. "It just tastes really good. It's not overly astringent, and it doesn't have any weird, funky flavors."

Do the math. Kopplin's general rule is three parts chocolate to one part cocoa powder. But he also suggests taste-testing. "It's not like 4-to-1 will be horrible," he said. "My rule of thumb is that you should use as little cocoa powder as you can get away with and still achieve the texture that you like."

Choose your milk wisely. For maximum hot chocolate lusciousness, Kopplin relies upon organic, nonhomogenized, grass-fed, cream-top milk. He prefers the Kalona SuperNatural brand. "It's a collection of Mennonite and Amish dairy farmers in Kalona, Iowa, and I really like what they do," he said. "It's super-delicious, a really consistent product."

Keep it whole. "That's my No. 1 recommendation, whole milk," he said. "Let's face it: Hot chocolate is not a health beverage. I also think that whole milk is a lot healthier than skim, but that's a whole other topic; we won't go there. But whole is a lot more delicious. Instead of ordering a 16-ounce low-cal skim-and-Splenda version of hot chocolate that you're not really enjoying, get an 8-ounce, made with great ingredients, that's totally enjoyable."

Watch the temperature. "At home, I put the milk on the stove on medium-low heat," he said. "The lower, the better, and the slower you can heat it up, the better." The ideal temperature: 145 to 150 degrees, tops. "You never want to boil milk," he said. "As milk heats, the lactose breaks down into simple sugars, but after 165 degrees you start to caramelize them. The milk loses its creaminess, and you end up with burned flavors." No instant-read thermometer? No problem. There's a less scientific way to monitor the milk's heat. "Don't wait for a bubble, because by then it's too late," he said. "Look for steam. You'll see steam at around 140 or 145 degrees."

Enlist the slow cooker. "If I'm going to get really fancy at home, I'll make my hot chocolate in the Crock-Pot," he said. "It's perfect for hot chocolate, because it heats so slowly. Besides, hot chocolate is one of those beverages that was really designed to be made at home, by Mom, in a big pot, ladled out."

Top it off. "I think marshmallows and whipped cream are both fantastic on hot chocolate," he said. "It's like everything else: If you're going to put it in, make it good." Right now, the garnish of choice at Kopplin's is a hefty crown of whipped cream, using that premium product from Iowa. No marshmallows. "We currently can't find any that we like," he said. "The ones that we do like, they're stupidly expensive. We're not just going to go and get a bag of Jet-Puffed, not that they're not delicious."

Serve it right. Does the shape of the cup make a difference? "Yes and no," he said. "Technically, does a mug versus a bowl make it taste any different? Not at all. But I fully believe that you taste with your mind. I say, pick your favorite cup and fill it up, because you're not only creating a drink, you're creating an experience."

Serves 4.

Note: Kopplin's Coffee owner Andrew Kopplin uses Callebaut or Valrhona chocolate and cocoa powder, and nonhomogenized whole milk from grass-fed cows.

• 1/2 c. finely chopped chocolate (see Note)

• 2 tbsp. plus 2 tsp. unsweetened cocoa powder (see Note)

• 4 c. whole milk (see Note)

• Freshly whipped cream or marshmallows for garnish, optional

Directions

In a small bowl, combine chopped chocolate and cocoa powder, and reserve.

In a saucepan over low heat, slowly warm milk, stirring occasionally, until steam appears, or an instant-read thermometer reads 145 to 150 degrees (do not bring to a simmer).

Remove from heat and add chocolate-cocoa mixture, whisking until chocolate is thoroughly combined. Pour into 4 cups or mugs, garnish with whipped cream or marshmallows, optional, and serve.