Galatoboureko (Custard Baklava)

For the citrus syrup:
1/2 cups sugar
1/4 cup water
2 Tbsp fresh lemon juice
1 slice orange (optional)

For the custard:
1 quarts milk
1/2 cup sugar
1/2 cup farina or Cream of Wheat cereal
1/4 cup (1/2 stick) unsalted butter
Pinch of salt
6 large eggs
1 tsp vanilla extract
1/2 tsp nutmeg

For the phyllo:
1/2 cup (1 stick) unsalted butter, melted
1/2 pound phyllo dough, thawed

1. To make the syrup: Add sugar, water, lemon juice and orange slice (if desired) to a heavy saucepan and simmer 10 minutes, skimming away any froth at the surface. Remove and discard the orange slice. Set aside to cool.
2. To make the custard: Heat the milk and sugar in a deep saucepan over medium-low heat, stirring with a wooden spoon. When the milk steams and is about to boil, shake in the farina. Add the butter and salt. Stir until the butter has melted and the mixture is thick and smooth, then remove from the heat and let the mixture cool to room temperature.
3. Beat the eggs and vanilla together in a large bowl until light, about 2 minutes. Stir in the cooled farina mixture, blending thoroughly.
4. Preheat the oven to 350°F.
5. To assemble the dish, brush a 11 x 9-inch baking pan with a thin coating of the melted butter. Unwrap the phyllo dough, laying it out flat on a clean surface, and covering it with a slightly damp kitchen towel to keep it from drying out.
6. Lay 1 half-sheet of phyllo dough on the bottom of the pan and brush it with a thin coating of melted butter. Continue layering and buttering the dough in the same manner for 8 half-sheets.
6. Pour in all the custard and spread it evenly. Cover the custard with 8 more half-sheet layers of buttered phyllo dough. Puncture the top sheets with a sharp knife in several places to allow the custard to breathe during baking.
7. Bake until the custard is set and the pastry shakes loose from the pan, about 30-45 minutes.
8. Let cool 30 minutes, then pour the sugar syrup over the pastry. Cool completely before cutting into triangles or rectangles. Serve at room temperature or chilled.