Melt the butter, add honey, vanilla sugar and a pinch of salt (if you like sweet things, you can increase the amount of honey). Stir.
In a bowl, combine the oat flakes, walnuts (pre-chop with a knife), flax seeds and Chia.
Pour the honey-oil mixture into the flakes.
Mix very well.
Put a uniform layer on a baking sheet (previously covered the baking sheet with parchment) and send it to bake in a preheated oven to 150 degrees.Bake for about 40-45 minutes. Every 10 minutes, mix the granola, taking the baking sheet out of the oven.
As soon as you see that the granola has become completely dry and Golden-take out the baking sheet from the oven.
Give it a little cool and add the raisins (raisins pre-pour boiling water, let stand, then drain the water and dry the raisins with a napkin). Mix again and allow to cool completely.The cooled granola is stored in a sealed container.