Preheat your oven to 325°F (160°C).
In a mixing bowl, combine the sweetened coconut, egg white, vanilla extract, and salt. Mix until the coconut is fully coated and holds together when pressed.
Press the coconut mixture firmly into the bottom and up the sides of a 9-inch pie dish.
Place the crust in the preheated oven and bake for 10-12 minutes, or until it turns lightly golden.
In a clean mixing bowl, whisk together the sweetened condensed milk, egg yolks, lime zest, and lime juice until smooth.
Pour the key lime filling into the cooled coconut macaroon crust.
Return the pie to the oven and bake for an additional 15-20 minutes, or until the filling is set but still slightly jiggly in the center.
Once baked, remove the pie from the oven and let it cool at room temperature for about an hour. Then, refrigerate for at least 3 hours or until fully chilled.
Slice the pie into wedges and serve chilled. Optionally top with whipped cream and additional lime zest.
