In a large glass, add the pineapple juice, coconut milk, key lime juice, and vanilla extract. Chill in the freezer for 20 minutes. Add the juice mixture to a blender along with the vodka, cubed pineapple, and coconut sugar. Blend on high until completely combined.
On a plate, gently stir together the coconut sugar and blanched almond flour. Take the slice of pineapple and rub it on the rim of the glass. Then roll the rim in the 'pie crust' mixture. Repeat with all three glasses and fill each with the blended martini liquid.
Recipe by PaleOMG - Paleo Recipes at http://paleomg.com/guest-post-frankensteins-key-lime-pie-martini/