Preheat the oven to 350 degrees
*Syrup* Bring the sugar and water to a boil over medium-low heat. Add the lemon peel, reduce heat to low, and boil gently for 12 minutes. Remove from heat, add lemon juice (do not stir) and remove from heat to cool.
*Filling* Using an electric mixer on high speed- beat 2 eggs with 1/3 cup of sugar until light and frothy, add 2 more eggs and another 1/3 cup of sugar, and repeat. Continue mixing for 2 minutes. Add semolina, lemon juice, and grated lemon peel. Continue beating and add the milk and 2 tablespoons of the melted butter. Beat for another 5-6 minutes until the mixture is light and fluffy.
Pour the filling into a large saucepan and heat over medium heat. Stir briskly with a whisk until filling thickens and can coat the back of a spoon. Remove from heat immediately and set aside.
*Assembly* (Use an 9 X 13" rectangular baking pan) Brush the bottom, sides, and rim of the pan with melted butter. Divide the package of phyllo dough in half. Half will be used on the bottom, half on top.
Lay one sheet of phyllo on the bottom of the pan and lightly brush with melted butter. Cover the remaining phyllo sheets with a damp towel to keep from drying out. Lay another sheet over the first and lightly brush with melted butter. Continue with the rest of the first half of the phyllo sheets.
Whisk the custard quickly and spoon over the layered phyllo sheets, spreading so it covers evenly and there are no gaps or air bubbles.
Using the remaining phyllo sheets, place them one at a time on top of the filling, brushing each with melted butter. When all the phyllo has been used, brush the top with butter.
Carefully cut the galaktoboureko into 16 pieces using a very sharp knife to cut all the way through to the bottom. Use a razor to make the first cut. The phyllo and custard filling are very delicate so cut carefully.
Bake on middle rack at 350 degrees for 30 minutes or until golden brown.
Remove from the oven and pour the cooled syrup evenly over the hot pastry. Set aside and allow to cool and absorb the syrup for 2 hours. Serve sprinkled with cinnamon if desired.
Yield: 16 pieces