Stuffed semolina cookies (ma'amoul)

Name: Stuffed semolina cookies (ma'amoul)
Prep time: 35 min
Cook time: 4 h
Total time: 4 h
Yield: 48 pieces
Ingredients: 600 g butter; 20 g dried instant yeast; 1000 g coarse semolina; 500 g fine semolina; 100 g white sugar; 6 pieces mastic gum; 14 mahlab (mahlepis) seeds; 150 g rose water; 70 g orange blossom water; 200 g water; 550 g shelled unsalted pistachio nuts; 30 g white sugar; 25 g orange blossom water; 50 g rose water; 100 g icing sugar