To toast coconut, spread it in a 9" x 13" pan, and bake it in a preheated 300°F oven for 18 to 22 minutes, stirring it halfway through, or until it's a light golden brown. Watch it very closely towards the end, as it'll go from golden to dark brown very quickly. Remove the coconut from the oven, and set it aside., Increase the oven heat to 350°F., In a large bowl, beat together the butter, sugar, vanilla, and egg. Mix in the flour, salt, baking powder, and 1 1/2 cups (80g) of the toasted coconut., Spread the mixture in an ungreased 9" x 13" pan. Bake for 15 minutes. Just before the 15 minutes is up, melt half the caramel; a VERY brief burst in the microwave makes this easy (probably 15 seconds or so)., Drizzle the melted caramel (or half the caramel sauce) over the crust and return it to the oven for 10 to 13 minutes; when done it'll be medium-brown and the caramel will be bubbly., Remove the crust from the oven and, working quickly, use a heatproof plastic knife (plastic reduces the drag in sticky baked goods), or a bench knife, to loosen the edges of the crust from the pan, and to cut 2 dozen bars, leaving them right in the pan. It's easier to cut these bars while they're warm., Sprinkle the bars with the chocolate. Allow the chocolate to soften for about 5 minutes, then spread it evenly atop the bars. Set aside to cool completely., Loosen the bars from the edge of the pan again, and use a flexible spatula to lift them out and set them on a rack., Combine the remaining caramel with 1 tablespoon milk or cream, and heat until the caramel is pourable. Stir to combine with the cream, and drizzle over the bars. (Or drizzle bars with the remaining caramel sauce.) Garnish with the reserved toasted coconut.