Preheat your oven to 350°F (175°C). Line a 9x9-inch baking pan with parchment paper.

In a food processor, combine the flour, macadamia nuts, brown sugar, and lime zest. Pulse until the nuts are coarsely ground. Add the cold butter and pulse until the mixture resembles wet sand.

Firmly press the crust mixture evenly into the bottom of the prepared pan. Bake for 15-20 minutes or until golden brown and set.

Whisk together the sweetened condensed milk, freshly squeezed lime juice, vanilla extract, and beaten eggs in a large mixing bowl. Gently fold in 2 cups of the flaked coconut and half of the lime zest.

In a small skillet, toast the remaining ½ cup of coconut over medium heat until golden brown, stirring frequently.

Pour the creamy filling mixture over the warm crust. Sprinkle the top with the toasted coconut and the remaining lime zest, pressing down gently.

Bake for another 15-20 minutes, or until the filling is set. Allow to cool completely in the pan before slicing into squares.