Put the pineapple, coconut, sugar substitute, egg whites, and salt into a medium saucepan and cook over medium-high heat, stirring constantly, for 5 to 6 minutes, until all of the liquid has evaporated and the mixture is sticky.
Remove from the heat, stir in the vanilla, and refrigerate for at least 1 hour or up to 2 weeks.
To bake the cookies, preheat the oven to 350°F with a rack in the Center position.
Coat a baking sheet with pan spray or line it with a silicone baking mat.
Scoop out tablespoon-size balls of the mixture to make about 30 cookies. If the dough is too dry to scoop, stir in 1 tablespoon water before scooping.
Arrange the cookies on the prepared baking sheet, spacing them about 1/2" apart (they will not spread).
Press an almond into the top of each cookie.
Bake for 20 to 25 minutes, until the cookies are golden brown. Halfway through the baking time, rotate the pan from front to back.
Transfer the cookies to a wire rack and let them cool completely, about 1 hour.
Melt the chocolate in the top of a double boiler until you can stir it smooth. (Alternatively, use a microwave oven.)
Spoon the melted chocolate over the cookies in a zigzag pattern. Allow the chocolate to harden before serving.