Sift the flour, baking powder and salt into a large bowl. Chop and rub in the butter. Add the milk and mix quickly to a soft dough with a knife. Turn out onto a floured board and roll into a square, about 30cm.
Mix the filling ingredients in a bowl. Sprinkle with the filling in an even layer, leaving about an inch bare on one of the sides. Roll up starting at the opposite edge and cut off into 1.5cm slices. Arrange together on a baking tray. Bake for 15 minutes until golden. Remove from the oven and allow to cool slightly.
Mix the glaze ingredients until a smooth paste. Bast the buns with the glaze and then sprinkle with the extra brown sugar.
I recommend eating these as soon as the last sprinkle of brown sugar hits the warm buns.
Recipe by Eatin' mess at https://eatinmess.com.au/recipes/chelsea-buns/