To Prepare the Cookies:
Utilize a stand mixer fitted with the paddle attachment to cream the butter and sugar together until the mixture is light and fluffy. This process incorporates air into the butter, contributing to the cookies' texture.
In a separate mixing bowl, whisk together the all-purpose flour, baking powder, and salt. Gradually add this dry mixture to the creamed butter in three increments, ensuring each addition is fully incorporated before proceeding. Scrape down the sides of the bowl as necessary to ensure even mixing. Following this, add the milk and vanilla extract, blending until the mixture begins to coalesce into large pieces.
Divide the dough into two equal parts, shaping each into a disk. Wrap these disks securely in plastic wrap and refrigerate until firm, approximately 1 hour. This chilling process is crucial for the dough's manageability.
Preheat your oven to 350ºF (175ºC).
Once chilled, roll out each disk on a lightly floured surface until they reach a thickness of 1/8-inch. Employ a doughnut-shaped cookie cutter to cut out the cookies. Place the cut-out cookies on a baking sheet lined with either a Silpat or parchment paper. Re-roll any remaining dough and repeat the cutting process.
Bake the cookies for 10 to 12 minutes, rotating the baking sheet halfway through the baking time to ensure even coloring. The cookies should be pale golden brown upon completion. Transfer them to a wire rack to cool completely.
To Prepare the Coconut Topping:
Distribute the shredded coconut evenly across a baking sheet lined with parchment paper. Toast the coconut in a preheated oven at 350ºF (175ºC) for approximately 10 minutes. It is imperative to stir the coconut frequently to ensure even browning and prevent burning. Remove from the oven once toasted and set aside.
Melt the caramels with milk and salt in a double boiler, ensuring the caramels are placed in a medium saucepot set over a larger saucepot of simmering water. Stir continuously until the caramels have fully melted. Remove from heat.
Combine three-quarters of the melted caramel with the toasted coconut in a large mixing bowl, reserving one-quarter of the caramel. Spread this reserved caramel atop the cooled cookies, then carefully press the coconut mixture onto each cookie. Allow the cookies to cool for 30 minutes. If the caramel-coconut mixture becomes too thick at any point, return it to the double boiler to warm until spreadable.
Melt the dark chocolate using a double boiler or microwave. Dip the bottoms of the cooled cookies into the chocolate and place them on a wax paper-lined baking sheet. Use a fork to drizzle chocolate over the tops of the cookies. Allow the cookies to sit until the chocolate sets completely.