Lightly grease a 9-inch springform baking pan with coconut oil.
Put the macadamia nuts, pecans, dates, salt, and vanilla in a food processor and process until the mixture is soft and easily workable. Press the mixture into the bottom of the prepared pan.
Make the filling:
Put the lime juice, agave, coconut milk, avocados, vanilla, salt, and coconut oil in a high-speed blender and blend until smooth.
Pour the filling over the crust, cover with plastic wrap, and freeze overnight. Thaw before serving.