Leave the butter and eggs at room temperture.
Add the butter into a mixing bowl and whip for 7 to 8 minutes.
In a seperate bowl, sift the flour and mix in the baking powder. Gradually add this mixture to the whipped butter and continue to beat until light and fluffy.
Remove the bowl from the stand mixer and add the masticha, orange zest, eggs, salt, and vanilla extract. Place the bowl back onto the stand mixer and mix until well combined.
Add the baking soda to the orange juice and stir until it bubbles. Once it is activated, pour it into the mixture and continue mixing.
Remove the bowl from the stand mixer and gradually add the flour, use your hand to mix gently until fully incorporated.
Cover with plastic wrap and chill for one hour.
Take one scoop of dough and roll out the dough into an even-size log about 6 inches long.
To shape the dough into the classic twist fold the log in half so the two ends meet. Then gently twist the strands together to form the braide.
Place on parchment paper and then brush with egg wash.
Brush each cookie with the egg wash.
Bake for 30 minutes or until golden brown.