Place the sugar, salt, cornstarch, and milk in a medium saucepan. Cook over medium-high heat, whisking/stirring almost constantly, until thick and bubbly (about 7-8 minutes), then reduce the heat to low and cook 2 minutes more.
Remove the pudding from the heat and stir in the butter, vanilla extract and 2 teaspoons coconut extract. Strain the pudding into a medium bowl to make sure no egg bits remain.
Stir in 2 cups coconut. Cover and chill for at least 30 minutes up to overnight.
To assemble the pie: place a thin layer of pudding on the bottom of the crust. Place sliced bananas in a single layer and then top with remaining pudding. Cover pie and chill for at least 2 hours or overnight.