01 - Preheat oven to 350°F. Line an 8-inch square baking pan with parchment paper, leaving overhang on two sides for easy removal.
02 - In a large bowl, whisk together melted butter and sugar until well combined. Add eggs and vanilla extract, beating until the mixture is smooth and glossy. Fold in cocoa powder, flour, salt, and baking powder until just combined — do not overmix.
03 - Spread the batter evenly into the prepared pan. Bake for 22–26 minutes, or until a toothpick inserted into the center comes out with moist crumbs. Allow to cool completely in the pan.
04 - While the brownies cool, spread the shredded coconut in an even layer on a baking sheet. Toast in the oven at 350°F for 5–7 minutes, stirring halfway through, until golden brown. Remove and set aside.
05 - Place the unwrapped caramel candies and milk (or heavy cream) in a microwave-safe bowl. Heat in 30-second intervals, stirring between each, until completely melted and smooth.
06 - Fold the toasted coconut into the melted caramel until evenly coated. Spread the mixture in a uniform layer over the completely cooled brownies.
07 - Place the chopped semi-sweet chocolate (and coconut oil, if using) in a microwave-safe bowl. Melt in 20-second intervals, stirring between each, until smooth and glossy.
08 - Drizzle the melted chocolate over the coconut-caramel layer in even lines. Allow the brownies to set at room temperature, or refrigerate until the chocolate is firm.
09 - Lift the brownies from the pan using the parchment paper overhang. Cut into 16 even squares and serve.