Mix the flour and salt in a bowl. Add the sugar and all other ingredients up to and including the egg and mix together. Knead to form a soft, smooth dough. Cover and leave to rise at room temperature until double in size.
Mix the nuts, sugar and cream thoroughly with the reserved lemon juice.
Assembling the loaf
Lightly flour the work surface and roll the dough out to approx. 30 x 40 cm. Spread the filling over the dough, leaving a border of approx. 2 cm on all sides. Roll up the dough from a narrow end and leave to chill for approx. 30 mins. Cut the roll in half lengthwise and braid the sections together with the cut sides facing up. Place the loaf in the prepared tin and leave to rise for a further 30 mins.
Baking the loaf
Approx. 40 mins. in the lower half of an oven preheated to 180°C. Remove from the oven, allow to cool a little then remove from the tin. Mix the icing sugar and lemon juice together thoroughly then glaze the still-warm loaf.