For the crust: In a small bowl combine 2 ½ cups of toasted coconut with brown sugar and melted butter. Mix well and press into the bottom and up the sides of a nine inch pie pan. Place crust in refrigerator.
In a small saucepan, combine the pawpaw, ½ cup sugar and triple sec. Cook over medium-high heat until sugar dissolves. Remove from heat and stir in lime juice, set aside. In a large bowl, beat the egg yolks on medium-high speed with an electric mixer until they become thick and pale yellow. Whip in the sweetened condensed milk, then stir in the pawpaw mixture. Pour into prepared pie shell and cover with plastic wrap. Refrigerate the pie at least 8 hours or overnight.
When ready to serve, whip the cream with 1 tablespoon of sugar and vanilla extract. Spread on top of the pie and garnish with remaining coconut.