Preheat an oven to 180 degrees C. Line a 20x30cm pan with aluminium foil.
Combine the oatmeal, raisins, sunflower seeds, wheatgerm, oat bran, linseeds, cinnamon and salt in the bowl of a mixer. Mix in peanut butter, honey and melted butter. Press mixture evenly into prepared pan.
Bake in the preheated oven for 15 minutes. Spread the melted chocolate chips over top; refrigerate until hard, about 30 minutes. Cut into bars.