Spelt Flour Cinnamon Rolls

(57)
"Made cinnamon rolls yesterday, having them for breakfast today."
-- @pinimarini
Dough:
530g spelt flour (type 630) + for working
1 package dry yeast
1/2 tsp salt
250ml spelt milk
70g butter
50g raw cane sugar
1 egg
 
Filling:
100g butter
100g raw cane sugar
2,5 tsp cinnamon 
 
Icing:
150g icing sugar
1 tbsp butter
3-4 tbsp spelt milk
 
Directions:
For the dough mix flour, yeast and salt in a large bowl. Heat up milk, sugar and butter in a pot without boiling it until the sugar and butter have melted. Mix this with the dry ingredients and knead roughly, afterwards add the egg and knead more thoroughly until the mixture becomes a smooth dough. If needed add flour.Cover the bowl with a wet towel and keep for 1 hour in a warm spot to grow.
Cover a baking or spring pan (around 30 cm in diameter) with baking paper.
In the mean time melt the butter for the filling, mix with sugar and cinnamon and set aside.
After the dough is grown knead it again and roll it out on a flour covered surface into a square (roughly 45 by 35 cm). Spread the butter mixture on the dough and cover it evenly.
Roll up the dough from below and cut into 10-12 pieces with each piece being 2-3 cm in size.
Put the buns into the pan with a little distance between each of them, cover the pan and let the buns grow for another 30 minutes.
Preheat the oven to 180°C and bake the buns for around 30 minutes. Afterwards let the buns cool down on a cooling rack.
While baking prepare the icing. Melt the butter in a pot, add milk and heat slightly before taking the pot off the stove. Mix the milk with the icing sugar thoroughly and keep mixing, until this becomes a spreadable icing mixture. Cover the buns while they are still warm.