If your beetroot is raw, put some gloves on, peel it, then coarsely grate it. If it’s already cooked, then wear the gloves and grate it. Place it in a pot with 150 ml of the vinegar, all but 1 Tablespoon of the sugar, the chilli and 250 ml of water. Bring to the boil then simmer for 5 minutes. Rinse the bean sprouts in cold water briefly, then place in a heat-proof jar or bowl. Strain the pickling liquid over them through a fine sieve and cover tightly while still hot. Leave to cool down then place in the fridge for at least 4 hours or up to a week.
Slice the lotus root ½ cm thick and rinse under cold running water for a few minutes, rubbing it a little to help release some of the slimy texture. Place in a saucepan and cover with cold water. Add the remaining vinegar and sugar, along with the soy sauce, ginger and star anise. Bring to the boil then simmer until cooked - at which point you’ll be able to just pass a sharp skewer through the flesh. Leave to cool in the liquor then store, covered, in the fridge for up to a week.
Rinse the rice with cold running water in a fine sieve for 30 seconds then place in a pot with 300 ml water, the sliced shiitake, 1 teaspoon flaky salt (less of fine salt) and cover with a tight-fitting lid. Place over high heat and bring to the boil, then turn the heat down, keeping the lid on, and cook for 15 minutes. At this point the rice should be cooked, the liquid should have evaporated, and the rice should be sticking to the bottom of the pan, turning golden and tasting toasted. If not, keep it cooking a little longer. Take the pan from the heat and, keeping the lid on, tilt it under a tap of running water to cool the base down. Alternatively, dunk the base of the pot into a bowl of cold water. Scrape the bottom bits up and mix into the rice then stir in the spinach and Parmesan and taste it for seasoning. Divide the mixture into eight 50 g portions and roll into a fat cylinder shape.
Take one enari pocket at a time and pull it gently apart. Tuck in one of the rice portions, gently flatten it into the enari to even it out, then dip the open mouth into 2 Tablespoons of the flour and press it firmly shut. This will help seal it. Do the same to the rest of the enari. Dust them gently with the other 2 Tablespoons of flour.
Make the tempura batter by sieving the remaining flour with the cornflour, baking powder and ½ teaspoon fine salt. Whisk in 120 ml cold water and leave for a few minutes - it will froth up a little but don’t worry.
Heat 6 cm of vegetable oil in a wok or pot to 180°C.
Give the tempura batter a stir, then dip the enari in, one at a time, to coat them then lower into the hot oil. You can cook four at a time, more if you have a huge deep-fryer. Take from the oil after 3-4 minutes at which point they’ll be golden brown and piping hot. Drain onto kitchen paper and cook the remainder.