The Science of Cooking with Chocolate

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Alice Medrich

Alice Medrich says one never needs an excuse to buy good chocolate. Courtesy of Alice Medrich hide caption

toggle caption Courtesy of Alice Medrich

Alice's Chocolate Sauce

Chocolate sauce can be divine with cacao of many percentages, but it requires adjusting. To find Alice Medrich's recipe for the perfect chocolate sauce for ice cream or poached fruit, click here.

Buying chocolate for baking used to be simple; there were semisweet, bittersweet and unsweetened varieties. No longer: Today, you can't be a true chocoholic without knowing about cacao. No, it doesn't have anything to do with coconut or stuttering cows — it's a measure of chocolate intensity. It's worth knowing about because a seemingly small difference in percentage can have dramatic consequences on the outcome of a concoction.

To temper the terminology of cacao, we turn to chocolate queen Alice Medrich. As we enter her kitchen in Berkeley, Calif., the site of many a divine dessert innovation, she is engaged in one of her favorite activities: chopping chocolate.

"That nice brittle snap is what chocolate makers like to have in their eating bars," she explains as dark brown squares crunch on marble. "That's why they make them thin. You can hear it crack, and it feels good between your teeth."

She slices the pieces small, so they won't burn — not that she would commit such a sin. A pastry chef and author of numerous award-winning cookbooks on chocolate, she has developed a sixth sense about it, she says.

"But, you'd be surprised. ... People are busy in their kitchen, and they don't know how easily chocolate can burn."

Burnt chocolate is a tragedy not only because it smells awful, but also because chocolate done right can facilitate an out-of-body experience.

No excuses are needed to consume high-quality chocolate, Medrich says. Nonetheless, all of the psychoactive theobromine (that caffeine-like stimulant in cacao that causes such happiness) in the world won't fix a bittersweet episode in the kitchen. Bittersweet is what an overzealous chef will get if he or she tries to sneak the new high-cacao chocolate into an old recipe.

"Sometimes when you upgrade a recipe to use better chocolate, it doesn't necessarily work out. That doesn't mean you throw away the recipe. If you want to use chocolate with a higher cacao content, you might have to revise that recipe," she says.

Understanding Cacao

What exactly is cacao? It's two things, actually: the cocoa powder and the cocoa butter from a cocoa bean. Together, they account for the total cacao percentage on the label of a chocolate bar. The rest is sugar, vanilla and whatever else the manufacturer has thrown in.

A higher cacao number on the label corresponds with a more intense chocolaty flavor in the bar. But a higher number is not always more delicious.

A chocolatier must be part scientist. Back in the kitchen in Berkeley, Medrich aims to address the question of how two chocolates with different levels of cacao will melt into the same amount of milk. Carefully measuring the milk and cacao, she prepares two sauces, side-by-side.

The Verdict

A few minutes later, the sauce with 55 percent cacao looks like liquid perfection.

"It's glossy. ... It would be beautiful to spoon over a dish of ice cream or a poached pear," she says. Medrich can't stop crooning over her creation: "It's gorgeous!"

The other sauce, with 70 percent cacao, looks like chocolate in a bad mood.

"Can you see that it looks a little almost curdled? That isn't a pleasant thing for a sauce," Medrich says.

In order to salvage her creation, she stirs in additional milk.

"Getting smoother!" she shouts.

Another chocolate catastrophe averted.

Medrich's Great Law of Cacao: The higher the cacao percentage of the chocolate, the more milk or cream needed to make the sauce smooth and fluid.

There's no reason to be cowed by cacao after all.

Elaine Corn reports for Capital Public Radio.

Alice's Chocolate Sauce

Cover of Bittersweet Book

Alice Medrich's book Bittersweet explores cacao percentages at length. She says that when it was first released, no one seemed to know what she was talking about, but now people are beginning to appreciate the significance of cacao. Courtesy of Alice Medrich hide caption

toggle caption Courtesy of Alice Medrich


10 ounces bittersweet or semisweet chocolate, chopped finely

1/2 to 1 cup milk, half and half or heavy cream, or any combination

2 tablespoons butter if using milk instead of cream, but optional

1/2 teaspoon vanilla extract, optional

pinch of salt

Put the chocolate and 1/2 cup of the milk or cream in a medium heatproof bowl set in a pan of not quite simmering water. Stir frequently until the chocolate is melted and smooth. Add more milk or cream if the sauce is too thick or looks curdled, or if it hardens too much when you spoon a little "test" over ice cream: the higher the cacao percentage of the chocolate, the more milk or cream you will need to make the sauce smooth and fluid.

If you are using milk, taste the sauce and add some or all of the butter, if you want to tone down the flavor intensity. Remove the sauce from the heat and stir in the vanilla and salt. Use the warm sauce immediately, or set it aside and rewarm it briefly in a pan of hot water when needed. Sauce keeps for several days in the refrigerator or may be frozen. Makes 1 3/4 cups.

Note: This versatile recipe can be tailored to your taste and the type of chocolate you are using. For the most intense sauce, use milk (with or without the addition of butter) rather than half and half or cream, and/or choose chocolate with a high percentage of cacao (66 percent to 70 percent or more). For mellower sauce, dial down the cacao percentage, and/or use half and half or heavy cream instead of milk.

From Bittersweet: Recipes and Tales from A Life in Chocolate (Artisan)

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