In a large mixing bowl, combine the plain flour, caster sugar, fast-action yeast, and salt.
Heat the milk until warm, then add the melted butter and egg. Mix well.
Pour the milk mixture into the dry ingredients and mix until a dough forms.
Knead the dough on a lightly floured surface for about 5-7 minutes until smooth and elastic.
Place the dough in a greased bowl, cover with a clean tea towel, and let it prove in a warm place for about 1 hour or until doubled in size.
In a separate bowl, mix the crushed Oreo cookies, softened butter, brown sugar, and ground cinnamon to make the filling.
Once the dough has doubled in size, punch it down and roll it out into a rectangle.
Spread the Oreo filling evenly over the dough, leaving a small border around the edges.
Roll up the dough tightly from the long side and slice into 12 equal pieces.
Place the rolls in a greased baking dish, cover, and let them prove for another 30 minutes.
Preheat the oven to 180°C (350°F).
Bake the rolls for 25 minutes or until golden brown.
Allow the rolls to cool slightly before serving. Enjoy!
