Happily, this dilemma reminded me of a recipe I used to make a few years ago. Overnight oats are all the rage at the moment but when I first made this it was known as Bircher muesli. Back then, I made it to take to work with me and had a cute insulated canister to carry it in (any excuse to buy a new item of kitchen kit!) but you really don't need this - any leakproof container will do, or just a bowl if you're eating at home.
I've been meaning to revisit overnight oats for a while, so my glut of apples provides me with the perfect opportunity. The raisins provide a pop of sweetness and the cinnamon pairs so well with the apples (think apple pie and mulled apple juice...mmmmm!).
If you're using rolled oats, it's best to leave them to soak overnight but if you use quick oats, which are more finely milled, they would be fine to eat after soaking for an hour or so. I prepare mine the night before because I find that easiest and I like the oats nice and soft. You can add the apple (along with maybe a sprinkling of nuts or seeds, or a dollop of yogurt) on the morning of eating if you prefer, but I don't think that's necessary because the apple doesn't go brown and yucky overnight as you might expect.
Apple, cinnamon & raisin overnight oats
1 tsp ground cinnamon
400ml milk of choice
Grate the apple (including the skin) into a large bowl. Add the oats, raisins and cinnamon and stir gently to combine.
Divide the mixture between two small bowls or 300ml capacity jars, then pour over the milk to cover. Transfer to the fridge overnight.