Preheat the oven to 160°C (325°F, gas mark 3). In a saucepan, combine the honey with the apple juice. Heat, stirring, until almost boiling. Remove from the heat and allow to cool.
Mix together the oats, wheat flakes, wheat germ and almonds on a baking tray. Pour over the honey mixture and toss until the grains and nuts are all coated. Spread out in an even layer.
Place the tray in the oven and bake, stirring occasionally, for 30 minutes or until toasted and golden brown. Remove from the oven and allow to cool, stirring occasionally.
Reduce the oven temperature to 120°C (250°F, gas mark 1⁄2). If using dessert apples, halve and core them, then thinly slice. Arrange the slices on two baking trays in a single layer.
Place in the oven to dry for 15–20 minutes, turning the slices once. Allow to cool slightly, then chop the apples coarsely. (If using dried apples, chop them coarsely.)
Combine the toasted grain mixture with the chopped apples, raisins and sunflower seeds. Store the cereal in an airtight container in the fridge for up to 1 month. Serve with semi-skimmed milk or plain low-fat yoghurt.