Place the eggs in cold water, bring to a boil then simmer for 8 min.
Cool under running water and set aside.
Fill a large bowl with hot but not boiling water, add the vinegar and food colouring and stir to dissolve. Add the cooked eggs ensuring they are completely submerged. Leave for 10 min or until the desired shade is achieved.
For the dough:
Zest the orange.
Place the flour, yeast, salt, butter and sugar into a large bowl. Add the mastic powder, mahlab and cinnamon, then the orange zest. Pour in half the water and milk and mix together briefly, then keep adding the liquid and mixing until you have a soft and slightly sticky dough.
Add the sultanas and mix through the dough, then tip out onto a lightly floured surface and knead until you have a pliable dough. Shape into a ball, place in a bowl and cover. Rest for at least an hour, or overnight in the fridge, until doubled in size.
Line a baking tray with baking parchment. Divide the dough into three and roll into three strands. Plait the strips together, place on the baking tray and leave to rise for another hour, or until doubled in size.
Preheat the oven to 210C/400F/Gas 6. Brush the top of the bread with egg wash and push the coloured eggs into the bread. Bake for 20-25 minutes, then transfer to a wire rack to cool.
«Mahleb and Mastic Gum are available from specialist delicatessens or online.»