1/2cupunsalted butter, plus 3 additional tablespoons (at room temp)
For the Filling:
zest of one lemon
5tbsp fresh lemon juice
Extra coconut for topping
Preheat oven to 350º. Grease a 13x9x2 metal baking pan with butter, shortening, or coconut oil.
Use an electric mixer to beat flour, coconut, powdered sugar, and salt until blended. Add butter and beat on low speed until clumps form. Press dough onto the bottom and slightly up the sides of the prepared baking pan. Bake crust until golden, about 25 minutes.
While the crust is baking, put sugar and lemon zest in a food processor and process until zest is finely ground. Add lemon juice and process to blend. Add eggs and process to blend. Add flour and a pinch of salt and pulse until mixture is smooth.
When crust is finished baking, reduce oven temperature to 325º, pour the filling over the hot crust, and return to the oven for 15 minutes. Remove and sprinkle additional coconut on top for garnish, if desired.
Return to the oven and bake an additional 15 minutes, until the filling is set. Cool in the pan on a rack.