Mix the yeast and the sugar with the milk. Leave for 10 minutes for the yeast to activate.

Break the eggs into a bowl and beat lightly.
Mix the flour, salt and lemon zest in a large bowl. Make a well in the centre and add the butter, eggs and yeast & milk mixture. Mix to a soft dough.

Knead the dough for at least 10 minutes then form into a ball and place in a lightly-greased bowl. Cover and leave in a warm place until the dough has about doubled in size.

Meanwhile, cut out a greaseproof paper. Place the paper on a baking sheet.
Once risen, turn the dough out onto a surface, knock it back knead for 2-3 minutes. Divide the dough into 4 pieces and form each piece into a ball.

Roll a ball of dough roll out into a circle. The dough should be about 3-4 mm (1/8") thick.
Place the dough onto the greaseproof paper and spread on a layer of Nutella, leaving a small gap at the edge. Don't make the layer too thick but be sure to evenly cover the dough.

Take a pair of adjacent segments. Lift and twist them away from each other through 180°. Lift and twist through 180° again, then twist through 90° so that the ends are vertical. Press the edges together firmly. Repeat this process for all pairs of segments.

Leave in a warm place for 1-2 hours to prove.
Brush with the glaze then bake at 160°C/320°F fan oven, 180°C/360°F conventional oven for 15-20 minutes.

Place the bread on a wire rack to cool. Once cooled, dust lightly with icing sugar.

#Notes:

Eat Nutella Brioche. It's great for breakfast and with a cup of coffee.

It you are going to mix the dough in a stand mixer let it run for 3 minutes during the initial kneading and just 1 minute for the second kneading.

If your Nutella is a bit difficult to spread simple place the jar in the microwave for 10-15 seconds with the lid loose, or place in a bath of hot water for 5 minutes.