Method:

• Make the yeast batter: In a stand mixer bowl, pour in the water and sprinkle over the yeast. Whisk to dissolve the yeast. Add the sugar and flour. Whisk again to combine. Cover with plastic wrap or a tea towel and let it stand for 10-15 minutes. During this time the mixture will have bubbles on the surface and it will rise. If it doesn’t, your yeast is not “working” and you should start over.
• Make the orange sugar: In a small blender blend sugar and orange peel on high speed. The sugar will take on an orange colour and all the aromas and oils from the orange peel will be extracted.
• Crush mastic seeds and mahleb seeds in a mortar and pestle or a coffee grinder.
• Make the dough: Place bowl with yeasted (risen) batter on mixer and attach the dough hook. Add lukewarm milk, orange sugar, vanilla, eggs, flour, crushed mastic and mahleb, salt and knead at medium-low speed for 10 minutes. Start adding the butter piece by piece. Knead 10-15 minutes more. Check the dough by pulling it. It should be soft and stretchy.
• Transfer dough in a buttered bowl. Cover and let it rise in a warm place for 2-3 hours until double in size.
• Shape the tsoureki: Divide risen dough in three or four equal pieces depending on how you want to braid the tsoureki. Roll each piece into a log. Join the top tip of the logs and braid the tsoureki (see note on braiding). Place it on a baking sheet on greaseproof paper or silicon mat. Cover with a tea towel for 30-45 minutes. In the meantime, pre-heat oven to 160 C fan.
• Brush the entire surface of the tsoureki with beaten egg. Sprinkle with sliced almonds if you like. Transfer in the oven and bake for 45-50 minutes. Cool (if you must!) and enjoy.