Mix all ingredients together carefully. Spread on a baking sheet lined with baking paper. Then bake in the preheated oven at approx. 120 degrees for about 40 minutes until light yellow. Now and then mix the muesli with a fork while baking. The muesli must not be baked too dark, otherwise it can become bitter. Let it cool down - now it gets really nice and crispy.
Then fill into an airtight can. The muesli can now be kept for a good 4 weeks.
It tastes great with milk, quark or natural yogurt. Raisins or all types of fruit can be added as desired.