For the dough, peel the sweet potato and dice it roughly. Cover with boiling water in a pot and simmer for about 20 minutes until soft. In the meantime chop the pecans coarsely. Chop the dates finely. Line a rectangular form (approx. 16 x 22 cm) with baking paper.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Drain sweet potato. Place the dates in a mixing bowl and puree finely with a hand blender. Stir in almonds, flour, cocoa and syrup.
Stir the pecans into the dough. Pour into the mould, smooth it down. Bake in a hot oven for 25-30 minutes (the brownie is ready when some of the dough still sticks to a wooden skewer or knife).
Remove and let it cool down.
For the icing, melt the cocoa butter in a hot water bath. Stir in coconut blossom sugar, cocoa and carob powder. Drizzle the icing over the brownie and then sprinkle with nuts, cocoa nibs and some sea salt to taste.
Allow to dry.