Place 1/2 cup water in a bowl of the stand mixer. Sprinkle the gelatin on top and let it bloom while you make the syrup.
Add the other 1/2 cup water to a small sauce pan and add in the maple syrup. Turn to medium heat and bring to a boil. Boil until mixture gets to 140°. I boiled mine for 10 minutes and it wouldn't go above 125° and it still set okay, but try to get to 140°. (UPDATE, try to get to 242°, but after 10 minutes of boiling it should work. I couldn't get mine that high)
Turn off the heat and let the bubbles stop. Stir in the cacao powder slowly and then add in the salt and vanilla. Turn the stand mixture on low to let the gelatin mix with the water. Slowly pour the hot mixture in and then turn the speed up to high. Beat until triples in size and light and fluffy- about 6 to 8 minutes. You don't want to beat longer than that or the marshmallow will get cool and hard to spread.
While that is mixing, prepare a pan. Grease the bottom of a small pan with coconut oil and then line it with parchment paper. This will help them not stick to it. Once mixture is done beating, scoop into prepared pan and smooth on top. Let sit to cool and then cut into squares. Mine was set within 30 minutes, but it may take longer.