Preheat the oven to 180 C (350 F). Place a dollop of coconut oil onto a baking tray and put into the oven to melt (about 2 minutes). Meanwhile peel and cube the sweet potato then throw onto the baking tray and toss, covering it with the melted coconut oil. Sprinkle with salt and roast in the oven for 25-30 minutes.
Place all of the dressing ingredients into a blender and whizz up into a smooth sauce. Pour into a lidded jar and chill until needed. (This recipe makes excess dressing).
While the sweet potato is cooking, put the quinoa into a fine mesh strainer and rinse. Then tip into a small pot along with 2/3 cup (160 ml) water. Season with a pinch of salt and bring to the boil. Lower the heat, cover and simmer for 10 minutes. Turn off the heat and leave it to sit, covered for 5 minutes.