Ultimate Turtle Brownies

To drizzle the caramel in step 4, use a 1⁄4-cup dry measuring cup that has been sprayed with nonstick cooking spray. If the caramel is too cool to be fluid, reheat it in the microwave.

1. FOR THE CARAMEL: Combine cream and salt in small bowl; stir well to dissolve salt. Combine water and corn syrup in heavy-bottomed 2- to 3-quart saucepan; pour sugar into center of saucepan, taking care not to let sugar granules touch sides of pan. Gently stir with clean spatula to moisten sugar thoroughly. Cover and bring to boil over medium-high heat; cook, covered and without stirring, until sugar is completely dissolved and liquid is clear, 3 to 5 minutes. Uncover and continue to cook, without stirring, until bubbles show faint golden color, 3 to 5 minutes more. Reduce heat to medium-low. Continue to cook (swirling occasionally) until caramel is light amber and registers about 360 degrees, 1 to 3 minutes longer. Remove saucepan from heat and carefully add cream to center of pan; stir with whisk or spatula (mixture will bubble and steam vigorously) until cream is fully incorporated and bubbling subsides. Stir in butter and vanilla until combined; transfer caramel to microwave-safe measuring cup or bowl and set aside.
2. FOR THE BROWNIES: Adjust oven rack to lower-middle position and heat oven to 325 degrees. Make foil sling by folding 2 long sheets of aluminum foil so that they are as wide as 9-inch square baking pan. Lay sheets of foil in pan perpendicular to one another, with extra foil hanging over edges of pan. Push foil into corners and up sides of pan, smoothing foil flush to pan. Grease foil and set aside.
3. Melt butter, bittersweet chocolate, and unsweetened chocolate in medium heatproof bowl set over saucepan of almost-simmering water, stirring occasionally, until smooth and combined; set aside to cool slightly. Meanwhile, whisk flour and baking powder together in small bowl; set aside. When chocolate has cooled slightly, whisk eggs in large bowl to combine; add sugar, salt, and vanilla and whisk until incorporated. Add melted chocolate mixture to egg mixture; whisk until combined. Add flour mixture; stir with rubber spatula until almost combined. Add chopped pecans and chocolate chips, if using; mix until incorporated and no flour streaks remain.
4. Transfer half of brownie batter into prepared baking pan, spreading in even layer. Drizzle 1⁄4 cup caramel over batter. Drop remaining batter in large mounds over caramel layer; spread evenly and into corners of pan with rubber spatula. Drizzle 1⁄4 cup caramel over top. Using tip of butter knife, swirl caramel and batter. Bake until toothpick inserted in center of brownies comes out with few moist crumbs attached, 35 to 40 minutes, rotating pan halfway through baking. Let brownies cool in pan on wire rack to room temperature, about 1-1⁄2 hours.
5. Heat remaining caramel (you should have about 3⁄4 cup) in microwave until warm and pourable but still thick (do not boil), 45 to 60 seconds, stirring once or twice; pour caramel over brownies. Spread caramel to cover surface. Refrigerate brownies, uncovered, at least 2 hours.
6. Remove brownies from pan using foil, loosening sides with paring knife, if needed. Using chef’s knife, cut brownies into 25 evenly sized squares. Press pecan half onto surface of each brownie. Serve chilled or at room temperature. (Brownies can be wrapped in plastic wrap and refrigerated for up to 3 days.)