Preheat the oven to 350°F (175°C) and lightly grease a 9x13-inch baking pan.

Prepare the crust by blending the flour, softened butter, granulated sugar, and salt in a mixing bowl until the mixture resembles coarse crumbs. Firmly press the crust mixture into the base of the prepared pan and bake for 15–18 minutes, or until it turns lightly golden.

For the filling, stir together the chopped pecans, shredded coconut, and chocolate chips in a bowl. Set aside.

In a medium saucepan, combine the granulated sugar, corn syrup, unsalted butter, beaten eggs, and vanilla extract. Cook over medium heat, stirring continuously until the mixture slightly thickens, approximately 5 minutes.

Pour the prepared filling mixture over the baked crust. Evenly scatter the pecan-coconut-chocolate mixture across the top.

Bake the assembled layers for an additional 25–30 minutes, or until the filling sets firmly.

As the bars bake, prepare the topping. In a small saucepan over low heat, melt together the sweetened condensed milk, unsalted butter, semisweet chocolate chips, and vanilla extract, stirring until smooth and well combined.

Once the bars are removed from the oven, immediately pour the warm chocolate topping evenly over the baked filling.

Allow the bars to cool completely on a wire rack before refrigerating for 1–2 hours, ensuring the topping sets firmly.

Slice into squares or bars and serve.