Preheat the oven to 325°. Line two half sheet pans with parchment paper and lightly spray with nonstick vegetable spray. Set aside.
In a large bowl, combine the egg whites, cream of tartar and salt. With a hand mixer, beat until soft peaks form. Gradually add the sugar, while continuing to beat the egg whites until the mixture is stiff and glossy. Add the extract at the end.
Add the coconut to the meringue mixture and mix until well combined.
Scoop out heaping tablespoon sized mounds of coconut mixture and place on the prepared baking sheet. Bake for 18-22 minutes or until the cookies are lightly browned.
Let rest on the pan for about 5 minutes before moving them to a wire rack to cool completely.
While the cookies are cooling, break up the chocolate into small pieces and place in a glass microwaveable bowl. Heat the chocolate in 15-20 second bursts in the microwave, stirring after each cycle, until the chocolate is melted and smooth.
Place a piece of clean parchment paper on a cooled baking sheet.
Dip the bottoms of the macaroons in the melted chocolate to coat the bottom and about 1/8" up the sides. Gently scrape off any extra drips back into the chocolate bowl. Transfer the cookies to the parchment lined baking sheet.
When you've finished dipping the macaroons, transfer the remaining chocolate into a zip-lock sandwich baggie. Snip off a tiny corner of the plastic bag and drizzle the chocolate over the macaroons.
Let the cookies rest about 30 minutes and then refrigerate for another 30 minutes so the chocolate is completely set.
I store my macaroons in the refrigerator -- but that's because I live in Florida and the chocolate wouldn't set entirely. If you live in a cooler climate, you may be able to store them in an airtight container at room temperature.