Grease a deep 23 cm/9 in springform cake tin. Sift the flour and cinnamon into a bowl, then rill) in the butter until the mixture resembles coarse breadcrumbs.
Stir in the sugar and yeast. In a jug or bowl, beat the egg yolk with the water and milk, then stir into the dry ingredients to make a soft dough.

  Knead the dough on a lightly floured surface until smooth, then roll out to a rectangle measuring about 40 x 30 cm/ 16 x 12 in.

  For the filling, brush the dough with the melted butter and sprinkle with the sugar, chocolate chips and nuts.

  Roll up the dough from one long side like a Swiss roll, then cut into 12 thick even-size slices. Pack close together in the tin, cut sides up. Cover and leave in a warm place for about I 1/2 hours, until well risen and springy. Meanwhile, preheat oven to 220°C/425°F/Gas 7.

  Bake for 30-35 minutes, until golden brown. Remove from the tin and cool on a wire rack. Brush with maple syrup while still warm. Pull swirls apart to serve.   View More