Make the lime filling the night before you want to serve this. You can also prepare the crust to the point where you freeze it the night before, if you like. Then simply bake the crust and fill the day you plan to serve it. Garnish with whipped cream or coconut cream and a bit more zest for a fun presentation.
Combine all filling ingredients in a high power blender and blend until completely smooth. Taste and adjust by adding more lime or sweetener as desired. Refrigerate overnight before using.
Toast the almond flour in a large skillet over medium high heat (this produces a better taste in the final product). It will brown slightly and smell nutty after about 5 minutes.
Stir all crust ingredients together, adding most of the butter, leaving a few tablespoons behind in a bowl until evenly mixed. The mixture should come together and form a ball when squeezed. If it crumbles add the rest of the melted butter - you want it just to stick together. Press into a 9-inch pie plate. Freeze for 15 minutes.
Preheat the oven to 400ºF while shell freezes. Then bake for 10 minutes, or until golden at 400ºF. Cool completely.