For the dough: Combine the yeast and milk in a bowl. Add the sugar and stir with a fork. Set it aside for 10-15 minutes at room temperature until it doubles in size. In a mixer's bowl, add the flour and pinch of salt. Begin beating on medium speed using the hook attachment. Add the risen yeast mixture and continue beating.
2
Melt the butter in a microwave for 1 minutes at 800 watts. Add it to the mixer while it is beating. Knead for about 10-12 minutes until becoming soft and elastic dough.
3
Brush the dough with some olive oil and transfer to a bowl. Cover with plastic wrap and set aside for 1 hour at room temperature.
4
After 1 hour resting, dust some flour onto your working surface. Roll out the dough into 30 x 40 cm rectangle. Turn the rectangle then the longer side is facing you and prepare the filling next.
5
For the filling: Purée the boiled beetroots in a blender and transfer to a strainer. Let it drain or place it in a thin kitchen towel and squeeze it to remove the excess liquid.
6
Spread it over the surface of the dough. Crush the pistachios in a blender or with a mortar and pestle, just to break them down a little. You don't want them finely ground. Sprinkle them over the beetroots puree. Coarsely crumble the feta cheese and distribute over the puree.
7
Roll the dough, beginning from the wide side that is frond of you to create a long log. Use a knife to cut it in half and lengthwise and carefully separate the 2 pcs. Since the dough is layered, you need to be careful the filling doesn't come out.
8
Brush 3-4 tbs of olive oil over the 2 pieces and braid them making sure that the cut edges are facing upwards.
9
Carefully transfer to a 26cm round cake pan with a whole in the middle. Set aside for 1 hour at room temperature. Preheat the oven to 180C. Bake for 30-40 minutes. When it's ready, remove from oven and let it cool in the pan for 10 minutes. Then turn out on to a wire rack and let it cool completely.