In a large bowl, dissolve the yeast in the water. Stir in the orange flower water, egg, and melted butter. Add the semolina and stir in, then sprinkle on the sugar and salt and stir. Add the flour and stir and turn to combine until crumbly but holds together when squeezed. Cover with plastic wrap and let rest for 1 hour.
Meanwhile, prepare the filling: Place all the ingredients in a food processor and process to a paste. Transfer to a bowl and set aside, covered.
Place a rack in the center of the oven and preheat the oven to 350°F Set out an 18 by 12 inch baking sheet near your work surface.
To shape the mamoul, use a tablespoon to scoop up a full level tablespoon of dough. Place it in the palm of one hand and use the thumb and fingers of the other hand to flatten it into a nearly 3-inch-diameter round. Scoop up 1 1/2 teaspoons of the filling and place it on the center of the round. Pull the edges up to cover the filling, then roll the cookie lightly between your palms to make a ball. Place seam side down on the baking sheet. Repeat with the remaining dough and filling, placing the cookies about 1/2 inch apart. Prick each cookie decoratively with a fork. Brush the tops with a little milk.
Bake until touched at the edges with golden brown, 20 to 25 minutes. Transfer immediately to a wire rack to cool. Makes 2 dozen rich cookies, either round mounds or high decorated ovals, filled with aromatic date paste.
NOTE: This recipe the instructions for round mamoul decorated only by pricking with a fork. In Syria and Lebanon, and in some specialty grocery stores in North America, you can find elaborately carved mamoul molds. If you have a mold, oil it with olive oil and then oil again lightly every 3 or 4 mamoul. Fill the mold almost full of dough and use your thumb to press down in the center. This will make a hollow in the center and will also give you thin walls of dough around the edges. You may need less filling, say 1 teaspoon each. Place the filling in the center, then fold the thin walls over and pinch off any excess dough. Pull the shaped mamoul up gently from the mold and transfer to the baking sheet, decorative side up. Repeat with the remaining dough and filling.
Semolina, a coarse grind of durum wheat with small, irregular yellow granules, is used to make pasta. It is also used as bread flour in Puglia, and in Tunisia and Morocco.
Semolina flour, also known as durum flour, is finely ground. It is very high in gluten. It can, like semolina, be used to make bread, but because it is so high in gluten, the bread dough will be stiff and the bread fairly tough.