Preheat the oven to 350°F (180°C). Grease an 8x8-inch (20x20-cm) baking pan and line with parchment paper.
Make the brownies: in a large bowl, whisk together the melted butter, granulated sugar, and brown sugar. Add eggs and vanilla extract. Whisk until thoroughly combined. Sift in the flour, cocoa powder, and salt, and fold to incorporate. Fold in the chocolate chips.
Pour half of the batter into the baking pan and spread to cover the bottom. Arrange the caramel candies in a single layer over the batter. Pour the rest of the batter over the caramel candies and spread to cover.
Bake for 35 minutes or until center is cooked through. Remove the brownies from the oven and let cool.
Make the topping: combine the caramel candies and heavy cream in a medium heat-proof bowl. Microwave for 1 minute in 30-second intervals, stirring between each until the mixture is thick and velvety.
Pour the caramel topping over the brownies. Let set for 10 minutes. Sprinkle with sea salt.