MAKE THE COOKIE BASE (OPTIONAL): To make chocolate shortbread cookies, cream the butter and sugar together in a large bowl until light and fluffy. Add the vanilla extract and mix well. Sift in the flour, cocoa powder, and salt, and stir until a soft dough forms. Shape into a disk, wrap in plastic wrap, and chill for 30 minutes. If using store-bought cookies or an alternate base, skip this step and begin with the topping.
ROLL AND CUT COOKIES (IF USING HOMEMADE BASE): Preheat oven to 350°F (175°C). Roll chilled dough on a lightly floured surface to ¼ inch thick. Use a 2.5-inch round cutter and a smaller cutter to make donut-shaped cookies. Place on a parchment-lined baking sheet.
BAKE COOKIES: Bake for 10 to 12 minutes, or until firm around the edges. Remove from oven and cool completely on a wire rack before topping.
TOAST THE COCONUT: Spread shredded coconut evenly over a parchment-lined baking sheet. Bake at 350°F for 8 to 10 minutes, stirring every 2 minutes until golden brown and aromatic. Let cool completely.
MAKE THE CARAMEL TOPPING: In a microwave-safe bowl, combine caramels and milk. Heat in 30-second intervals, stirring between each, until melted and smooth. Add salt if needed. Stir in the toasted coconut until fully coated.
ADD TOPPING TO COOKIES: Spoon the caramel-coconut mixture over each cooled cookie, using your fingers or a spoon to press it into place. Let cookies sit for 5 to 10 minutes for the topping to set slightly.
MELT THE CHOCOLATE: In a microwave or double boiler, melt chopped chocolate with optional coconut oil. Stir until smooth and fully melted.
DIP AND DRIZZLE: Dip the bottom of each cookie into the melted chocolate and place on parchment paper. Drizzle additional chocolate across the tops using a spoon or piping bag.
LET SET: Allow cookies to set at room temperature for 30 minutes or chill for 15 minutes until the chocolate is firm and the topping is fully set.