In reply to OneBeardedWalker:
You’re really disadvantaging yourself if you limit to unprocessed foods. Apart from them being heavy, you’re either likely be eating lots of fiber (depends on your GI) or lots of fat.
If the intensity is high, you just need simple carbs. There’s no way round it.
I see you mentioned multi day events. Perhaps worth looking into your calorific needs and your goals. Out of all options, Lucho Dillitos, Chia Charge flapjacks and Spring Energy gels are the least evil.
For a reference, I aim for 90-120g of carbs an hour for both training and racing up to 24hrs. Let’s say 100g/400kcal is a round number and let’s use calorie equivalents (as very few unprocessed foods will have carbs only). For a 20hr run, that’s 1.1kg of macadamia nuts or 2.5kg of dried mango (that also has 60g of fiber).