Preheat the oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer) and line two baking trays with baking paper. For the chocolate syrup, chop 100 g chocolate coarsely. Bring 125 ml water and 125 g sugar to the boil in a saucepan and simmer for 3-4 minutes until the sugar has dissolved.
Take it off the stove. Stir in 50 ml sunflower oil, 3 tablespoons honey, chocolate and 1 pinch of salt until the chocolate has dissolved. Leave to cool slightly.
Coarsely chop 100 g nuts. In a large bowl, mix with 500 g crunchy oats and 100 g coconut flakes. Pour syrup over it and mix so that all ingredients are covered with syrup.
Spread the muesli evenly on the trays. Bake one after the other in a hot oven for about 20 minutes. Remove from the oven and let it cool down. Pour into a large sealable jar or a tin. Crunch with milk or yoghurt and fruit.