Preheat your oven to 180C/365F.
In a ramekin or small baking dish, layer the bottom with frozen blueberries and raspberries.
In a bowl, mix the plant milk, cinnamon, date/maple syrup and oats and combine well.
Pour the oats mixture over the berries and top with walnuts.
Place it in the oven and cook for about 25-30 minutes, or until crispy.