Wisk together milk, first 2 eggs, brown sugar and cocunut milk. Whip until smooth.
Add other eggs and rum extract, whip until smooth again, stir in pineapple.
Coat a 9 inch pie pan, with nonstick spray, place in baking pan, large enough to hold, pour custard into pie shell. Fill baking pan with water until it reaches halfway up the sides of the pie pan (water baking).
Bake for 1 hour at 350 degrees.
Sprinkle with coconut and refrigerate for 2 hours before serving.