Here's the recipe:
¼ cup plus 2 tbsp heavy cream
¼ tsp salt
¼ cup water
2 tbsp corn syrup
1 ¼ cup granulated sugar
2 tbsp unsalted butter
½ tsp vanilla extract
½ cup unsalted butter, cut into pieces, plus more for pan
4 ounces semisweet chocolate chips
2 ounces unsweetened chocolate, chopped
¾ cup all-purpose flour
½ tsp baking powder
¼ tsp salt
2 large eggs
1 cup granulated sugar
2 tsp vanilla extract
20 pecan halves, toasted
1. For caramel: Pour cream into a glass measuring cup; stir in salt to dissolve. In a small heavy saucepan over medium-high heat, combine water and corn syrup. Gently stir sugar into pot. Cover and bring to a boil. Cook for 4 minutes, until sugar is completely dissolved, without stirring. Uncover and cook for 4 minutes, without stirring. Reduce heat to medium-low. Cook for 2 more minutes, until golden and a candy thermometer registers about 360 degrees F.
2. Remove pot from heat and carefully pour cream into center of pot. Mixture will bubble vigorously; stir until cream is incorporated. Once bubbling eases, stir in butter and vanilla. Lightly coat a glass measuring cup with butter; pour caramel into prepared cup.
3. For brownies: Preheat oven to 325 degrees F. Set oven rack to lower-middle position. Line a 9-inch square baking pan with foil or parchment paper, letting foil hang over sides of pan. Lightly butter bottom and sides of foil.
4. In a medium heatproof bowl, combine butter, semisweet and unsweetened chocolates. Microwave until melted, stirring at least once; set aside to cool.
5. In a small bowl, whisk flour, baking powder and salt. In a large bowl, whisk eggs, sugar and vanilla until blended. Whisk cooled chocolate mixture into egg mixture. Fold in flour mixture until blended. Pour batter into prepared pan. Drizzle about ¼ of the caramel over top. Using tip of a knife, swirl caramel and batter. Bake for 35 minutes, until a toothpick inserted into center comes out with a few moist crumbs. Transfer to a wire rack to cool.
6. Warm remaining caramel (you should have about ¾ cup) in microwave until pourable to still thick (do not boil), stirring once. Pour caramel over brownies; evenly spread caramel. Refrigerate brownies, uncovered, for at least 2 hours.
7. Using foil extensions lift cold brownies from pan. Run a knife around edges of brownies to loosen sides from foil (caramel may stick). Peel away foil. Using a sharp knife, cut brownies into squares. Press a pecan half onto middle of each brownie.
Connie's tips: Pour the finished caramel directly into a glass measuring cup that has been sprayed with nonstick spray or coated with butter. This makes for safe reheating in the microwave, foolproof pouring and easy clean-up. Also: the 35 minute cooking time seemed way too short. I continued cooking the brownies, checking every five minutes or so, until they were done, probably another 15 minutes or so.