In a food processor, using the dough hook attachment, combine Ground Flaxseed (2 tablespoon), Water (6 teaspoon), Vegan Butter (10 tablespoon), All-Purpose Flour (1 1/2 cup), Powdered Confectioners Sugar (1/2 cup), Vanilla Extract (1/2 teaspoon), Unsweetened Cocoa Powder (1/4 cup), and Kosher Salt (1/4 teaspoon).
Process, pulsing and scraping down the sides occasionally until well combined and collects on one side of the bowl.
Press evenly into a 9 inch tart pan, ensuring the dough is brought all the way to the top edge of the pan. Poke with a fork several times, and place in the refrigerator to cool for one hour.
Meanwhile, for caramel, place Vegan Sugar (1 1/2 cup), Light Corn Syrup (3 tablespoon), Water (5 tablespoon), Kosher Salt (1/4 teaspoon), Coconut Extract (1/4 teaspoon), and Rum Extract (1/4 teaspoon) in a small bowl. Set aside until ready to use.
Preheat the oven to 350 degrees F (175 degrees C).
Remove the tart from fridge and place pie weights on top of the crust to keep it from ballooning while baking. Bake for 20 minutes, then remove weights and bake for 8-10 minutes.
Remove from oven, and chill until ready to use.
Now, in a heavy bottomed soup pot, add the bowl of caramel ingredients and heat over medium flame. Continuously stir until combined, then allow to cook until it's reached 350 degrees F (175 degrees C). It should boil, without stirring, until it's dark amber.
Remove from heat, and stir in the canned Full-Fat Coconut Milk (1/2 cup) and Vegan Butter (1/4 cup) until smooth. Pour into the chilled tart crust and place in the fridge.
For ganache, in a pyrex measuring cup or microwave-safe bowl, heat the Coconut Milk (3/4 cup) for 1-2 minutes until very hot. Add Semi-Sweet Vegan Baking Chocolate (8 ounce) and whisk until smooth.
Pour the ganache over the caramel (careful it doesn't overflow!) and place on a level surface in the fridge to chill, at least 1-3 hours depending on if it was pre-chilled or not.
Remove once chilled and finish with a sprinkling of Sea Salt Flakes (to taste). Slice and serve chilled. Store in the fridge, as the tart will become oozy if let out of the fridge for too long, but will stay very firm if chilled.