Preheat barbecue grill to high. Put sweet potato in a steamer basket and immerse in a large saucepan of boiling salted water. Cook for 3 minutes or until almost tender. Drain and set aside to cool slightly.
Lightly grease grill with oil. Add potato, in batches, and cook for about 3 minutes on each side, or until lightly charred and cooked through. Set aside to cool and season with salt and pepper.
To make creamy aioli dressing, put all ingredients in a small bowl and stir to combine. Season with salt and pepper. Set aside.
Put almonds, chives, chilli, oil, lemon zest and juice and parsley in a medium bowl and stir to combine.
To serve, smear dressing over the base of serving platter. Arrange sweet potato on top. Spoon over nut and herb mixture.1. Put 1 sugar cube in each of 8 Champagne flutes. Add 2 drops of Angostura Bitters to each cube. Stand for 5 minutes to allow bitters to soak into sugar cubes.