Chocolate Hazelnut Swirl Brioche

A really lovely dessert loaf that my family loved.  It is a bit of work as the brioche dough takes time, but it is well worth the effort.  Hazelnut works well but could easily be substituted for walnut or almond.  From Food and Drink Holiday 2015.

FILLING
1/4 cup hazelnuts, lightly toasted and skins removed
1 tsp egg white
2 tbsp icing sugar
1/4 tsp vanilla extract
2 oz semi sweet chocolate, coarsely chopped

1 recipe Brioche (bottom of recipe)
1 egg beaten with 2 tsp water

• Place hazelnuts in the bowl of a food processor and grind until fine.  Add the egg white, icing sugar and vanilla and blend until pasty.  Add the chocolate and blend until finedly chopped.  Set the filling aside.
• Butter the sides of an 8 x 4 inch loaf pan and line the bottom with parchment paper.  On a floured surface, roll the dough lengthwise, to a 7 x 18 inch rectangle.  Brush cold water very lightly over the dough.  Top with the chocolate nut filling, within 1/4 inch of the borders.  Roll over the dough once very gently just to embed the filling.
• With the short side facing you, fold the top edge of the dough over about 1/2 inch.  Using both hands, roll the dough toward yourself, tucking it under with your thumbs to tighten as you work your way down the entire log.  As you tuck, try to keep the roll taut and even.  Wrap the dough in wax or parchment paper and place in the freezer just to firm up slightly, about 10 to 15 minutes.
• With the seam side down and using a sharp knife, cut the dough in half lengthwise.  Gently stretch each portion of dough until it is about 12 inches long.  Place the dough strips lengthwise and parallel to one another on the table making sure the filling is facing up.  Starting at the top, overlap the ends of the dough and gently pinch them together.  Cross the pieces over one another 3 to 4 times, pinching the ends together at the bottom.  Transfer to the prepared loaf pan.  Cover the pan loosely with plastic wrap and place in a warm place until the loaf is almost doubled in bulk, 1 1/2 to 2 hours.
• Preheat the oven to 350F.
• Brush the beaten egg lightly over the top of the loaf and bake until deep golden brown, about 40 minutes.  Cool on a wire rack, then remove from pan.

BRIOCHE

Sponge

3/4 cup bread flour

1/4 tsp rapid rise instant yeast

2 tbsp cold, unsalted butter, cut into 1/4 inch pieces

5 tbsp milk

Final Dough

3/4 cup bread flour

1 tsp salt

3/4 tsp rapid rise instant yeast

2 tbsp plus 1 tsp sugar

2 medium eggs

6 tbsp cold, unsalted butter, cut into 1/4 inch pieces

• For the sponge, combine the bread flour and yeast in the bowl of a stand mixer fitted with paddle attachment.  Add the butter and milk, and mix on low speed until well combined and no butter lumps remain, 1 to 2 minutes.  Cover the surface of the dough loosely with plastic wrap and allow to stand for 30 minutes.  The fermentation will begin during this time, but the sponge will not expand to any noticeable degree.
• For the final dough, place the flour, salt, instant yeast and half the sugar in a bowl and whisk to combine.  In another bowl, whisk the eggs just to break them up.  Add the dry mixture along with the eggs to the sponge and mix on low speed with the paddle attachment until the mixture is combined, about 1 minute.  Replace the paddle with the dough hook and mix the dough on low speed for 5 minutes.  Increase the speed to medium and mix for an additional 8 minutes, stopping to scrape down the sides of the bowl and the dough hook 1 or 2 times.  Add the remaining sugar and mix to incorporate.
• Add the butter in 3 additions, mixing until fully incorporated.  The dough will be very soft and shiny.  Wrap in layers of plastic wrap and refrigerate overnight.
• The dough can be held in the fridge for 2 days or frozen for 2 weeks.  Thaw in the fridge overnight before using.