In a medium saucepan, pour in the chocolate, oat milk, maple syrup and pinch of salt. Turn the heat to medium-low and warm slowly, whisking steadily, until the chocolate has melted and has married with the oat milk.
Carefully transfer to the blender and pour in the scoops of collage, if using.
Place the lid on and allow some steam to escape (if you don’t, it can sometimes lead to a bit of an explosion) and pulse for about 30 seconds, until nice and frothy.
Divide amongst mugs and serve.