For the yellow macaron shells: • powdered sugar (150 g) • almond flour (150 g) • large egg whites, divided (about 110 g, split into 2 portions of 55 g each) • mineral water (37 g) • granulated sugar (150 g) • small amount of yellow food coloring • For the white macaron shells: • powdered sugar (150 g) • almond flour (150 g) • large egg whites, divided (about 110 g, split into 2 portions of 55 g each) • mineral water (37 g) •