Yam tempura is one of my favorite dishes, and it's easier to make than you think!
Preheat your vegetable oil in a deep flat-bottomed pot or deep fryer to 365°F.
In a large mixing bowl, combine rice flour, paprika, chilli powder, sea salt and ground black pepper. The most important part is that the soda water must be cold before incorporating it into the batter. The colder the batter, the lighter and crispier the texture. Only add the cold soda water to the rice flour mixture when the frying oil has reached its cooking temperature. Fold it into the batter with a spatula a few times. Do not over mix the batter, as it will cause the soda water to flatten.
Lay out some paper towel on a plate near your frying station beforehand. Submerge a few pieces of the sweet potato into the batter and lift it out with a fork to allow the excess batter to drip off before frying it in the oil.
Cook the pieces of battered yam for approximately 4 minutes in the oil before removing with a slotted spoon and placing on the paper towel to cool.
Continue deep frying in batches. I recommend keeping the batter in the fridge between batches.
hot tip: make sure your soda water has been in the fridge or freezer prior to preparing this recipe. It needs to be really cold before frying. Tougher root vegetables tend to take a bit longer to cook so if you're using the batter on something like asparagus or onions, only cook for 3 minutes.