Ingredients
1   coconut    
1/2   cup (1 stick) unsalted butter, at room temperature    
2   cups sugar    
4  large eggs    
2/3   cup buttermilk    
1   teaspoon pure vanilla extract    
2  tablespoons freshly squeezed lemon juice    
2   teaspoons freshly grated lemon zest 

Directions
1. While the sugar crust is being refrigerated, test each of the three eyes at the stem end of the coconut to see which is the softest. Then, use an ice pick or a screwdriver and a hammer to pierce two of the eyes. Strain water through a fine sieve into a bowl; reserve for another use or discard.  

2. Place coconut on a rimmed baking sheet; bake for 30 minutes, or until coconut shell begins to crack. Set aside until cool enough to handle. 

3. Wrap coconut in a clean kitchen towel; holding coconut with one hand, hit it with a hammer in the same place several times to crack the outer shell and split the coconut into several large pieces.
 
4. Separate coconut flesh from shell, and use a vegetable peeler to remove the dark outer skin. Using the large holes of a box grater, grate the coconut, creating long shaved pieces about 1/4 inch wide. You will need 1 1/4 cups; chill remaining coconut in an airtight container for another use.  

5. Remove crust from refrigerator. Cover with parchment, and fill with pie weights or beans. Bake for 15 minutes. Remove from oven, and let cool. Increase oven temperature to 400.F. 

6. Prepare the custard: In the bowl of an electric mixer fitted with the paddle attachment, cream butter and sugar until light and fluffy. Add eggs one at a time, beating until pale yellow and creamy. Add buttermilk, vanilla, and lemon juice, beating until well combined. Mix in lemon zest and 1 cup shredded coconut. 

7. Pour mixture into pie crust. Sprinkle with remaining coconut, and bake for 10 minutes. Reduce heat to 350.F, and continue baking until pie is golden brown and custard is set, 35 to 40 minutes. Let cool slightly before serving.  Serves 8.   
 
Sugar Crust  
2   cups all-purpose flour    
1  cup confectioners’ sugar    
3/4  cup (1 1/2 sticks) unsalted butter, chilled and cut into pieces    
1/4  teaspoon salt    
2  large eggs 
Preheat oven to 350.F. In the bowl of a food processor, combine flour, sugar, butter, and salt; process until mixture resembles coarse meal, 15 to 20 seconds. Add eggs one at a time, and process until dough just comes together. 

Press dough into a 10-inch round tart pan with a removable bottom. Cover with plastic wrap, and refrigerate for at least 1 hour.  Serves 8.
   
Source:  www.marthastewart.com