Tip: To get a smokier flavor in the stock, you can dry roast your onion and scallions.
For the rice wine, ratio is generally 1 teaspoon rice wine to 1 tablespoon soy sauce.
Hot pot:
Ingredients of your choice e.g. udon noodles, bok-choy, kai-lan, carrot, zucchini, eggplant, cabbage, silken tofu, enoki mushrooms, scallions, etc.
Tip: You can save the kombu and shiitake mushrooms for topping.
For the stock:
Place the onion, garlic, scallion stems, shiitake, kombu, ginger, peppercorns and water in a pot. Bring to a roiling boil and then reduce heat.
Simmer on low heat until the flavor of the stock is at a level you like. Generally around 3 hours.
Keep checking the water level of your stock every so often. Add more water as you need.
For hot pot:
If using, boil your noodles. While the noodles are cooking, wash and prepare your veggies.
Once the noodles are finished, drain and wash away the starch. Put them into a ceramic pot/hotpot pan and ladle enough stock on top to cover them completely.
Season the stock with the sesame oil, soy sauce, rice wine, miso and salt.
Layer your veggies on top and turn on the heat. Bring to a boil and then simmer until the veggies are all cooked. Serve.

Stock:
7-8 cups of water
1 onion
8 cloves garlic
8 shiitake mushrooms, dried
Two large handfuls of small kombu sheets or 3-4 large sheets
Stems of 3 scallions
1 tablespoon ginger powder
2 tablespoon white peppercorns, adjust to taste
Salt to taste
1 1/2 teaspoon white miso
Sesame oil to taste
Light soy sauce to taste
Rice wine