Preheat your oven to 325°F (165°C). Line two large baking sheets with parchment paper.

In a large mixing bowl, combine the sweetened shredded coconut, sweetened condensed milk, and vanilla extract. Use a rubber spatula to stir until the coconut is thoroughly coated.

In a separate, completely clean and grease-free bowl, beat the egg whites and salt using an electric mixer on high speed until stiff peaks form (the peaks should stand straight up when you lift the beaters).

Gently fold the whipped egg whites into the heavy coconut mixture using a rubber spatula. Fold carefully to keep the batter aerated until no white streaks remain.

Use a cookie scoop to portion the mixture into 1.5 tablespoon-sized mounds. Pack the dough tightly into the scoop so the cookies hold their shape.

Drop the mounds onto the prepared baking sheets, spacing them about 1 inch apart.

Bake for 20-25 minutes, or until the bottoms and the outside edges of the coconut are deeply toasted and golden brown.

Remove from the oven and let the macaroons cool completely to room temperature directly on the baking sheets. Do not move them while hot.

Once cooled, place the chopped dark chocolate in a microwave-safe bowl. Heat in 30-second increments, stirring well after each, until smooth and fully melted.

Dip the bottom of each cooled macaroon into the melted chocolate.

Place the dipped macaroons back onto the parchment paper. Transfer the baking sheets to the refrigerator for 15 minutes to set the chocolate completely.