Mix the nut milk and the lemon juice or ACV together in a small bowl/measuring cup. Set aside - this will make the vegan buttermilk.
In a large bowl, whisk the gluten free flour, baking powder, baking soda, salt and pumpkin pie spice.
Add the flax egg, brown sugar and pumpkin into the vegan buttermilk mixture and whisk until just combined and smooth. Pour into the dry ingredients and mix together until just mixed, folding over to fully incorporate. Add in the chocolate chips and fold over one more time. The batter will thicken slightly while you wait for the griddle pan to heat up.
Heat a griddle pan or a cast iron skillet over medium heat and brush with coconut oil or vegan butter.
Pour about ¼ cup of batter into the pan/skillet for one pancake. Wait until some bubbles start to form on top, then pop. Allow to cook for 2-4 more minutes and then flip the pancakes over. Cook for about 2-4 more minutes until batter is cooked through.
Serve pancakes hot and drizzle with maple syrup on top and your favorite toppings.