Preheat the oven to 200°C.
Wash plums and pit them, then place in a ovenproof dish.
Sprinkle the plums with stevia, grounded cinnamon, nutmeg and saffron, do not mix.
In a small pot, melt the butter.
Set spelt flour, coconut, chia and vanilla in a bowl, then add the melted butter. Mix quickly until big crumble pieces appear.
Sprinkle the crumble over the fruit, place in the oven and bake for around 40 minutes or until golden brown.