Ingredients for Truffle Brownie batter
Preheat oven to 325 degrees. Line a buttered 8-inch square baking pan with foil or parchment paper, allowing 2 inches to hang over sides. Butter lining (excluding overhang); set pan aside.
Make batter: Follow steps 2 through 5 of the Truffle Brownies recipe.
Pour caramel over brownies; spread with an offset spatula. Refrigerate until cold, 30 minutes to 1 hour.
Let brownies stand at room temperature at least 15 minutes before serving. Lift out brownies, and cut into 8 rectangles (2 by 4 inches each), wiping knife with a hot, damp cloth between each cut.
Topping
1 cup sugar
1/3 cup heavy cream
1 teaspoon pure vanilla extract
1/2 teaspoon slat
1 cup coarsely chopped toasted pecans (4 ounces)
Bring 1/3 cup water and the sugar to a boil in a medium saucepan over medium-high heat, stirring, until sugar has dissolved. When water comes to a boil, stop stirring, and wash down sides of pan with a wet pastry brush to prevent crystals from forming. Continue to cook, swirling pan occasionally, until mixture is medium amber, 5 to 7 minutes.
Remove from heat, and immediately add cream, vanilla, and salt. Gently stir spatula until smooth. Add pecans; stir until caramel begins to cool and thicken slightly, about 1 minute.
