Melt the butter in a small pot over low heat and set it aside.

Preheat the oven to 180ºC (350ºF) and generously butter a 25x35cm baking dish.

Lay one filo sheet on a clean surface and brush it generously with melted butter.

Crumple the buttered sheet loosely with your fingers into a ruffled fan shape.

Place each crumpled filo sheet into the prepared baking dish, arranging them side by side until the dish is full.

Bake in the preheated oven for 20 minutes until the filo turns golden and crisp.

While the filo bakes, whisk together the condensed milk, water, and 1 teaspoon of cinnamon in a bowl until smooth.

Remove the dish from the oven and pour the condensed milk mixture evenly over the baked filo, making sure it seeps into all the crevices.

Return to the oven and bake for another 20-25 minutes until the cream has set and the top is golden brown.

Let it cool for 10 minutes, then dust generously with icing sugar and a sprinkle of cinnamon before serving warm.