Preheat oven to 325 degrees. Line a baking sheet with parchment and set aside.
Using an electric mixer with a whisk attachment, beat egg whites, sugar and vanilla until frothy. (Approximately 2 minutes).
Pulse shredded coconut in a food processor for 30 seconds. Note: coconut needs to measure 4 1/2 cups after pulsing.
Fold coconut into egg white mixture, stirring with a rubber spatula until moistened.
Using your hands or a large cookie scoop, shape mixture into balls and space one inch apart on prepared baking sheet.
Bake for 10 minutes, rotate pan and bake for an additional 8 to 10 minutes or until tips and edges begin to lightly brown.
Cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Melt chocolate in a heat-safe bowl in the microwave in 30 second intervals until melted and smooth. Dip bottoms of macaroons in chocolate then place on parchment-lined baking sheet. If desired, drizzle tops with melted chocolate. Refrigerate to set.
Store chocolate dipped coconut macaroons in an airtight container at room temperature up to 3 days or in the refrigerator up to 1 week.
Macaroons can be frozen in an airtight container up to 3 months. Thaw overnight in the refrigerator.
