Peel and weigh your daikon, then shred it. You can shred them as finely or as coarsely as you like, this depends on your preferece for texture;

Prepare the rice flour slurry, add the rice flour in a mixing bowl, slowly pour in th water while stirring until no lumps or dry flour left, set aside;

Heat a drizzle of oil in a skillet or frying pan over medium-high heat, saute the chopped scallion whites for a minute or so until aromatic;

Add in the shredded daikon and chopped shiitake mushrooms, add in the saute to help the vegetables release their juice, cook until the vegetalbes are soft and most of the liquid has evaporated and absorbed;

Add in the white pepper, chopped scallion greens and a handful of chopped smoked tofu, this is optional, you can skip it if you have trouble finding smoked tofu;

Turn the heat to low, slowly pour in the rice slurry, and stir the mixture simultaneously, until the vegetables and the rice flour slurry are completely and evenly combined. You'll notice the mixture is thickening quickly, keep stiring and cooking for another minute, turn off the heat and remove your pan;

Oil your steaming container or mold and line with parchment paper, transfer the mixture into the mold, gently press down, smooth out the top, sprinkle on some more chopped smoked tofu and sesame seeds if you like;

Bring the water in your steamer to boil, transfer the turnip cake in the steamer and steam on high heat for 10 minutes then medium-low heat for another 10 minutes, the total cooking time depends on your stove, steamer, and how high is your mold, test the doneness by inserting a toothpick in the middle of the turnip cake, if it comes out clean that means it's ready;

Let the turnpi cake completely cool down before demolding and cutting, you can leave it in the fridge to cool down overnight;

Once the turnip cake is set, flip it over and remove from your mold, slice, and you can serve them as is or lightly pan fry the slices in a pan for 1-2 minutes each side, serve with a dipping sauce, enjoy!