The evening before, soak the chia seeds with a teaspoon of oatmeal in milk and place in the refrigerator overnight.
Thaw the raspberries or heat them in a saucepan. Let the raspberries simmer until they are mushy. Put in a bowl. Now cut the apple and mix the chia pudding and yogurt in the bowl with the raspberries. Mix in oatmeal, flaxseed and, if necessary, a little sugar or cinnamon.
You can add to the muesli as you like; cashew nuts, for example, go very well with it.