Pour the coconut milk into a small saucepan, and heat over medium-high heat until boiling, about three minutes. Whisk regularly to prevent burning.
Reduce the heat, bringing the coconut milk to a gentle simmer, then add the agave syrup, whisking until it is completely dissolved.
Simmer for 30-45 minutes, stirring often, or until the liquid is reduced by half.
Remove from the heat and allow to cool completely before using.
For the Crust
Preheat the oven to 350 F (175 C).
In a medium bowl, combine the graham cracker, almond meal, sugar, and salt.
Add the coconut oil and stir until the crumbs are evenly coated.
Press the crumb mixture evenly into the bottom and up the sides of four four-inch tart shells.
Bake the crusts until lightly browned, about eight minutes.
Remove the pie crusts from the oven and cool on a rack in the dish for 15 minutes, and then refrigerate until well chilled, about one hour.
For the Whipped Coconut Cream
Chill your coconut milk in the refrigerator overnight, being sure not to shake or tip the can to encourage separation of the cream and liquid.
The next day, chill a large mixing bowl 10 minutes before whipping.
Remove the coconut cream or milk from the fridge without tipping or shaking and remove the lid. Scrape out the top, thickened cream and leave the liquid behind (reserve for use in smoothies).
By hand, whisk together the coconut milk, icing sugar, and xanthan gum until thick and sticky. Keep everything very cold for the best results.
Transfer to a blender and blend on high speed until light and aerated. Refrigerate until ready to use.
For the Filling
Make the filling just before serving to prevent oxidation or separation. In a blender, blend the avocado, lime juice, condensed coconut cream, lime zest, vanilla, and salt, until smooth and silky.
To Serve
Remove the crusts from the refrigerator and release them from the tart pans (use a blowtorch if needed).
Spoon the filling into the crusts about a quarter-inch (six mm) from the top.
Transfer whipped cream to a piping bag, pipe over half of the top of the tarts.
Garnish with lime slices, serve immediately. Enjoy!