Pop your popcorn kernels in an air popper if you have one. Otherwise, pop your corn using the stovetop method (see link above) or in a microwave using packaged vegan microwaveable popcorn. Place popped popcorn in a large bowl and set aside--this should amount to roughly 11 cups of popped corn.
Preheat oven to 200 degrees Fahrenheit.
Line 2 cookie sheets with parchment paper or nonstick silicon liner, and set aside.
In a small sauce pan, place coconut milk, mayple syrup, cane juice crystals, vegan butter, and salt.
Place saucepan on medium heat and gently stir with a nonstick spatula or wire whisk.
Stir every 15-20 seconds as mixture comes to a boil.
Continue stirring frequently as mixture comes to a boil. Once mixture has been boiling for 5 minutes, check the texture, by dropping a few drops of boiling caramel on to your parchment lined sheet pan. If caramel remains liquidy when individual drops are placed on a cool surface, you know it needs to boil longer. If caramel becomes sticky and stringy when a drop of it is placed on a cool surface, then you know it is ready. As one final check before mixing the caramel in your popcorn, drizzle a few drops of caramel sauce on to a piece of popcorn. If the popcorn doesn't shrivel up, and the caramel is still fairly sticky/stringy, then it's ready for your baking powder (which is optional). Quickly stir in baking powder, and remove caramel sauce from heat.
Slowly drizzle over your popped popcorn while stirring.
Quickly mix caramel sauce and popcorn until popcorn is fairly evenly coated. This becomes more difficult to do as the caramel cools and becomes thicker. Spread popcorn onto parchment lined cookie sheets (I recommend using 2 cookie sheets for a thinner layer of popcorn) or roll popcorn into balls.
Bake popcorn at 200 degrees Fahrenheit for 50-55 minutes
Allow popcorn to cool completely for several minutes before eating or storing. Store in an airtight container for 1 week, but I guarantee you it won't last that long.