For the cookies: Preheat the oven to 350 degrees. Spread the coconut in an even layer on one half of a rimmed baking sheet and the pecans on the other. Toast, stirring coconut halfway through, until nuts are fragrant and coconut is light golden, 5 to 7 minutes. Place coconut and pecans in a food processor and pulse until finely chopped (alternately you can chop very finely by hand).
In a large bowl beat the butter and sugar together until light and fluffy. Beat in vanilla. Add flour and salt; beat until combined. Beat in chopped coconut and pecans. Turn out the dough onto a piece of plastic wrap and shape into a flattened disk. Wrap in plastic. Chill the dough until firm, about 30 minutes.
Line two large baking sheets with parchment paper or slipat liners. Set aside. On a lightly floured surface, roll out the dough to about 1/8-inch thickness. Using a 2-inch flower (or round) cookie cutter, cut out shapes and place 1 inch apart on baking sheets. Chill until firm, about 10 minutes.
Remove from fridge or freezer and using a smaller (about 3/4-inch) round cookie cutter or wide end of a pastry tip cut out and remove the centers from half the cookies.
Bake the cookies until golden brown, about 12 minutes. Transfer cookies to a wire rack to cool completely. Cookies can be made 1 day ahead and kept in an airtight container at room temperature.
For the caramel filling: Place the sugar and 1/4 cup plus 2 tablespoons water in a medium heavy-bottom saucepan. Set over medium-high heat and stir to combine. Without stirring, bring the mixture to a boil, and cook until dark amber in color, about 5 minutes, washing down the sides of the pan with a wet pastry brush to prevent crystals from forming (click here and scroll down about halfway for a good visual image of this process).
Remove from heat. Carefully pour the cream down the sides of the pan (it will spatter), stirring constantly, until fully combined. Add the butter and stir to combine. Transfer to a heatproof bowl and let cool slightly before filling the cookies.
When cookies have cooled (don’t start the caramel until they are cool), spoon or pipe about 1 teaspoon caramel filling onto the flat side of each of the whole cookies. Top with cut cookies, keeping flat sides down. Drizzle the remaining caramel over the tops. Let caramel set for at least 2 hours. The cookies can also be drizzled with melted chocolate, if desired. Cookies can be kept, layered between sheets of parchment paper in an airtight container at room temperature for up to three days.