Prepare the Syrup: In a saucepan, combine equal parts sugar, lemon juice, and lemon zest over medium heat. Stir continuously until the sugar fully dissolves; this should take about 5 minutes. Once dissolved, remove from heat and let it cool completely while you prepare the custard.

Make the Custard: In a large pot, whisk together fine semolina and whole milk over medium heat. Continuously stir the mixture as it heats to prevent lumps from forming, cooking until it thickens to a pudding-like consistency, about 10-15 minutes. Once thickened, remove from the heat and stir in eggs and vanilla extract until smooth, creating a rich custard.

Layer the Phyllo: Preheat your oven to 350°F (175°C) and prepare a baking dish by brushing it generously with melted butter. Carefully unroll the phyllo dough, placing a sheet into the dish and brushing it with more melted butter. Continue layering 6-8 sheets of phyllo, making sure to brush each layer with butter for that perfect flaky texture.

Add the Custard: Once your phyllo base is layered and brushed, evenly pour the creamy custard over the top. Use a spatula to spread it gently, ensuring it reaches the edges. Then, start layering additional phyllo sheets over the custard, brushing each one with melted butter, so the top layers have the same delightful crispiness as the base.

Bake the Galaktoboureko: Transfer the assembled Greek Galaktoboureko to the preheated oven and bake for approximately 50 minutes, or until the top is golden brown and crisp. Keep an eye on it towards the end to ensure it doesn’t over-brown.

Soak in Syrup: Once removed from the oven, pour the cold syrup evenly over the hot pastry, allowing it to soak in. Let it cool at room temperature for at least one hour before slicing.

Serve and Enjoy: After cooling, cut the Galaktoboureko into squares or rectangles for serving. This dessert is best enjoyed at room temperature or chilled, perfect for pairing with a cup of Greek coffee or a strong black tea.