Brown ox tail in nut oil with a touch of sesame oil(easy). Remove ,fry chopped onions in pan drippings. Then add ginger ,garlic ,fry gently just for a minute. A slug of chinese rice wine let it bubble.Then add stock,star anise, cinnamon stick ,sichuan pepper,orange zest & juice,your choice of sugar thats palm.Then the tricky bit ,you want enough soy sauce to colour it but not over power it & you have to watch the salt content because it will concentrate as it reduces.I add about a tab of hoi sin sauce.
This going in a cast iron casserole pot & in the oven for I don't know .
You want to cover the meat so don't skimp on stock.
This is out of my head after looking at a few hot pot recipes so bear with me.
If I can get to the local chinatown today I will see if there is lotus root & those white northern noodles.The chinatown 5 minutes from me is very northern lot of noodles,pancake,chilli ,steam boat ,hot pot even a specialty lamb restaurant called the little sheep!