Preheat the oven to 350 degrees F. Line a 13-inch by 9-inch rectangular baking pan with parchment and grease with butter.

In a medium saucepan, bring 1 inch of water to a low simmer. Place the butter and chocolate in a large heatproof bowl over the saucepan without the water touching the bottom of the bowl. Stir frequently until the mixture is fully melted and then remove from the heat. Stir in in the vanilla extract and salt.

In a large bowl, use an electric mixer to beat the eggs and sugar until light and fluffy, about 3-5 minutes. Fold into the chocolate mixture followed by the flour.

Transfer the batter to the prepared pan using a spatula to spread in an even layer. Sprinkle the top with pecans. Bake for 35-40 minutes. Cool the brownies completely before drizzling with caramel sauce (recipe below).

For the caramel, combine the sugar and water in a large saucepan. Cook over medium heat without stirring until the mixture starts turning deep amber and then carefully swirl the pan, about 20 minutes. Remove the caramel from the heat. Add the heavy cream and stir until it stops bubbling. Add the butter.