1. Make sure the milk is lukewarm and stir in the yeast. Leave to one side for 5-10 minutes.
2. Lightly beat the aquafaba with an electric hand whisk until bubbly and frothy and slowly add in the sugar while whisking. Continue to whisk as you pour in the melted butter and vanilla.
3. Place the four and salt in the bowl of a free-standing electric mixer with the dough hook attached. Pour in the yeast mixture and the aquafaba mixture and knead for 10 minutes on a low setting.
4. Once soft, springy and shiny, remove the dough, place in a greased bowl and cover. Leave to double in size in a warm place for about 2 hours.
5. Meanwhile, divide the chocolate spread into half tea spoon amounts, place on parchment paper and freeze to solidify and then lightly dust with flour. Chop the hazelnuts.
6. Prepare a 20 cm round tin with parchment paper.
7. Pour the dough onto a lightly floured work surface and grease your hands a little with oil. Add the chocolate spread balls and hazelnuts to the dough and knead for 3-4 minutes with your hands to incorporate the chocolate and hazelnuts. Transfer to the lined tin, cover and leave somewhere warm for 45-60 minutes to increase in volume (it will expand to fill the tin).
8. Preheat the oven to 160/180C. brush the dough with the milk , sprinkle over the chopped hazelnuts and bake for 45-50 minutes until really golden and crispy on top and risen.
9. Allow to cool on a wire rack. to serve, slightly warm the chocolate spread, drizzle over the pannetone, sprinkle over the hazelnuts and dust with icing sugar.
10. Store wrapped up in an airtight container for a few days.