Line 7–8 muffin or pudding cups with paper cases. Set aside.
Cut sweet potato into small cubes. Place in a small saucepan and add 2 Tbsp beet sugar. Pour in just enough water to cover. Simmer until sweet potatoes soften, then drain and set aside.
Sift both flours and baking powder together.
Place remaining beet sugar, sea salt and yam in a bowl