Combine the sugar, water, and salt in a medium saucepan set over medium heat. Stir occasionally with a fork until mixture comes to a boil, about 3-4 minutes. Continue to simmer until mixture becomes a medium amber color, about 5-6 minutes, swirling pan every so often. Immediately add the cream, and reduce the heat to medium-low.
Using a heat-resistant spatula, constantly stir the caramel until mixture is smooth, about 3-4 minutes. Turn the heat off, stir in the vanilla, and allow to cool/thicken for about 5 minutes.
Preheat the oven to 325ºF and line a baking sheet with parchment paper. Stir the coconut into the caramel.
In the bowl of a stand mixer fitted with the whisk attachment, whip the egg whites on high until stiff peaks form. Gently fold whipped egg whites into the coconut mixture.
Using a small cookie scoop, drop rounded (and compacted) tablespoons of the coconut mixture onto the lined baking sheet about an inch apart. Bake for 15 minutes. Allow to cool at least 10 minutes on the baking sheet before transferring to a wire rack to cool completely.
Line a baking sheet with wax paper. Melt the chocolate and the coconut/vegetable oil together either in the microwave or over a double broiler, stirring until smooth. Dip the bottom of each macaroon into the chocolate, then place onto the wax paper-lined baking sheet. Drizzle the remaining chocolate over the tops of each cookie, then chill in the refrigerator until chocolate is set.
*You can find finely shredded unsweetened coconut in the health/organic foods section of most grocery stores or in the bulk section.