This is a very sweet coconut cream pie with a soft and creamy filling. It makes a lot and will fill a deep dish pie crust, so if you are using a smaller pie crust you'll have a bit of leftover filling. If you are using something like storebought Keebler crusts, you can probably fill two.
With this recipe, you'll be making the meringue first. Be sure to have all of your filling ingredients and equipment lined up and ready to go so that the meringue doesn't sit for too long.
Preheat oven to 325 degrees F. and have ready a rimmed baking sheet to set the pie on.
In a large mixing bowl, beat the egg whites and cream of tartar until peaks just start to form, then very gradually add the sugar. Continue beating just until the mixture holds stiff peaks. Set aside.
In the top of a double boiler off the heat, stir together the sugar, cornstarch, salt and egg yolks. Gradually add cold milk, whisking until smooth. Meanwhile, begin heating water in the lower part of the double boiler.
Set the top of the double boiler over the simmering water. Cook, whisking vigorously to help break up and dissolve the egg yolks, until very thick -- almost as thick as cooked pudding or rich cream gravy. Temperature should be around 183 degrees F. It should not boil and it won't seem thick enough to hold, but you are going to bake it for 30 minutes so it will get more heat.
Once hot and thick, remove from the heat and stir in the butter, ¾ cup of coconut and vanilla. If using coconut extract, add that too. Pour hot mixture into the baked pie shell.
Carefully spoon meringue over, sealing the edges the best you can. Sprinkle remaining coconut over the top.
Set the pie on the rimmed baking sheet and bake at 325 degrees F. for about 30 minutes. Let cool, then chill for several hours or overnight. This makes enough for a fairly deep dish pie.
Notes
For a homemade graham cracker crust, mix together 1 ½ cup graham cracker crumbs, ¼ cup sugar, 1 pinch of salt and ⅓ cup melted unsalted butter. Press into bottom and up sides of a shallow 9 inch pie tin. Bake at 350 for about 8 minutes.