Preheat the oven to 160°C (315°F). Dig out a high-sided 15 x 25 cm (6 x 10 inch) tray. (This isn’t a non-negotiable size — just note that the bigger the tray, the thinner and snappier your oaty bars will be.) Grease the tray with cooking spray, or brush oil or a little butter up the sides and then a smidge in the base. Press a sheet of baking paper over the base; the oil will help stick the baking paper neatly in place, so your bars don’t get random waves in the bottom.
In a large mixing bowl, combine the oats, nuts, seeds, coconut and dried fruit (and/or choc chips). Sprinkle in the salt flakes and sugar and mix well.
In a small saucepan, combine the honey, butter, vanilla paste and ½ cup (125 ml) water, bringing this delicious concoction to the boil. As soon as it starts to bubble and smell like honeycomb, add it to the dry mixture and stir well.
Pour the mixture into the tray and press down. You might even like to place a sheet of baking paper over the top and really press down with the flats of your hands to get a lovely smooth finish. Pull this piece of baking paper off before transferring to the oven, but keep it handy for wrapping bars or keeping layers separate.
Bake for 30 minutes, or until golden brown. The slab will be a bit puffy and HOT, so it needs to cool in the tray a little, before you can again place your baking paper over and press down with the flats of your hands to compress the mixture a little to get an even, pro-looking result. Feel free to leave the surface puffy and rustic, if you’d prefer.
Chill in the fridge before cutting into squares or bars. Store in the fridge in an airtight container, with baking paper separating the layers. The bars will keep in the fridge for up to 10 days. They may go a little bendy, but will still taste great.