Salted Caramel Popcorn Brownies

Name: Salted Caramel Popcorn Brownies
Prep time: 30 min
Cook time: 30 min
Total time: 1 h
Cuisine: American
Ingredients: ¾ cup all-purpose flour; ¼ cup dutch-process cocoa powder; ¾ teaspoon baking powder; ½ teaspoon kosher salt; 6 ounces unsweetened chocolate (do not use bittersweet, chopped); ¾ cup unsalted butter; 1 ½ cups granulated sugar; ¾ cup packed dark brown sugar; 4 large eggs; 1 teaspoon vanilla extract; 1 cup chopped bittersweet chocolate; 1 tablespoon olive oil; 1 teaspoon kosher salt; ⅓ cup popcorn kernels; 1 cup granulated sugar; 2 tablespoons light corn syrup; ½ cup heavy cream; 4 tablespoons unsalted butter; 1 teaspoon finishing salt (like Maldon, fleur de sel or coarse sea salt)