Roughly chop the hazelnuts, pumpkin seeds, figs, and prunes (or chop finely if you prefer a finer texture). Grate the apples.
Put the flour and oatmeal in a bowl. Add the water, oil, chopped nuts and seeds, grated apples, raisins, sunflower seeds, salt, honey, and cinnamon. Knead everything together into a dough.
Line a baking sheet with parchment paper and spread the dough evenly across it.
Bake in a preheated oven at 180 °C (356 °F) for 30 minutes.
While the dough is still warm, cut it into 20 portions and allow them to cool completely.
Store the bars in a tin or airtight container, using parchment paper between layers to prevent them from sticking together.