Combine all the ingredients in a large bowl and mix well.
Store in an airtight container or jar — it'll keep for a few weeks in a cool, dry place, ready whenever you need breakfast in a hurry.
To serve cold: spoon a portion into a bowl, add milk, yoghurt, or your dairy of choice, and let it sit for a few minutes so the oats soften slightly. For a creamier, Bircher-style bowl, mix your portion with milk or yoghurt the night before and leave it in the fridge overnight.
To serve hot: add a portion to a pan with milk or water and warm gently for a few minutes, stirring occasionally — or simply pour hot milk over it and let it steep for a minute or two. A good option on a cold camping morning.