Grease a 25-cm ring tin or tube pan with butter or non-stick cooking spray. Combine 150 g (1 1/4 cups) flour, half the caster sugar and all the salt in a bowl.
Heat milk with 4 tbsp butter until lukewarm. Sprinkle on the yeast to dissolve; stir into the flour mixture. Stir in the egg. Add enough flour (at least 425 g) to work into a soft dough.
Turn dough out onto a lightly floured work surface; knead for about 10 minutes until elastic; add remaining flour to keep dough from sticking. Melt remaining butter. Mix remaining caster sugar, the brown sugar and the cinnamon in a bowl.
Pull off pieces of dough the size of a golf ball, arrange in a single layer in the pan and brush with half the melted butter. Sprinkle top with half the sugar mixture. Repeat for a second layer. Cover with a damp cloth towel. Leave to rise in a warm place until doubled in size, about 30 minutes.
Preheat oven to 190°C.
Bake bread for about 35 minutes or until browned on top. Stand pan on a wire rack; cool for 10 minutes; unmould and serve rolls warm.