Preheat your grill to medium-high heat or prepare your campfire coals.
In a small bowl, combine the chia seeds with the water. Let the mixture sit 5-10 minutes or until it has thickened and is goopy.
To a large mixing bowl, combine the oats, almond meal, maple syrup, baking soda, salt, softened butter and vanilla extract. Add the chia seed mixture and then mix well, making sure the oats are well moistened. Stir in the chopped chocolate.
Slice the peel of each banana from stem to bottom, almost all the way through the banana itself. Essentially, cut the banana in half lengthwise, but leave it connected at the bottom.
Carefully open the banana peel just enough to spoon the oatmeal cookie dough mixture inside. Stuff the dough generously, allowing some to spill out.
Wrap each stuffed banana tightly in aluminum foil. Place them on the grill or directly in the hot coals of a campfire. Cook for 8-10 minutes, until the chocolate is melted and the dough is cooked. For a crispier topping, unwrap the foil slightly during the last few minutes of cooking.
Unwrap carefully, open the peels wide, and serve immediately with a scoop of ice cream. Eat with a spoon!