Divinity candy is an American creation that appeared on the scene right around the same time as corn syrup, in the early 20th century. No surprise there, since the relatively flavourless syrup is a key ingredient in the confection. In fact, early Karo cooking brochures apparently featured a divinity recipe, and the current Karo website does too.
Corn syrup has been a pariah of the food world these past few years. For a straightforward discussion on when you might want/need to use corn syrup as well as David Lebovitz's personal philosophy on the issue (which I share), check out his 2009 post titled Why and When to Use (or Not Use) Corn Syrup. Obviously 1/2 cup of corn syrup is hardly a judicious quantity, but I don't see myself making chocolate divinity candy a habit. So what the heck.
After the fact, I learned that divinity candy can be a bit fickle when it comes to setting. Mine seemed to hold its shape just fine, although it remained quite soft (think Three Musketeers). Having nothing to compare it to, I declare my version a victory.
Chocolate Divinity Candy
4 ounces semi-sweet chocolate, coarsely chopped
1/2 cup water
2 cups sugar
1/2 cup white corn syrup
2 egg whites
1/4 teaspoon salt
1 teaspoon vanilla
Line a cookie sheet with lightly greased parchment paper. Set aside.
Melt chocolate in a heatproof bowl over barely simmering water, stirring until smooth. Remove from heat and set aside.
In a medium saucepan, combine water, sugar and corn syrup. Boil over high heat, without stirring, until the temperature reaches 255 degrees Fahrenheit.
While the sugar mixture is boiling, whip the egg whites and salt in a large heatproof bowl until foamy.
When the sugar mixture reaches temperature, carefully pour it into the egg whites in a steady stream while beating on medium-high speed. (It's best to pour the hot liquid down the side of the bowl so that it doesn't splash up.)
Once all the liquid has been added, beat on high speed until glossy, thick and cool (about 7 minutes). Beat in the melted chocolate and vanilla.
Use a pastry bag with an extra wide tip, or a Ziploc bag with the corner snipped, to pipe small peaks onto the prepared cookie sheet. Let sit at room temperature for 2 hours before packing the divinity candy away in an airtight container.
Candy will keep for up to one week at room temperature.
Source: Food & Drink, Holiday 2009, p. 110.