1. 300ml (10.1oz) of dry soybeans weighs 240g (8.5oz). When fully soaked, the weight of the beans becomes about twice of the original weight. In my case, it weighed 500g (17.6oz).
2. When rehydrated, my mushrooms weighed about 50g (1.8oz).
3. The diameter of my lotus root was 5-6cm (2"-2 3/8") so I cut each slice into 6 pie shapes. If much larger in diameter, you would need to cut each slice into more pieces so that the size of each piece is similar to the other vegetables.
4. The time required to cook soybeans varies depending on how firm/soft you want the beans to be. You can check it by eating a bean from time to time.
5. A drop lid is called otoshi buta (落し蓋) in Japanese. It is a round lid which is slightly smaller than the opening of a saucepan. It is traditionally made of wood but I have a stainless steel lid. It is placed on top of the ingredients in a pot to ensure the heat is evenly distributed, ingredients cook faster, and stay in place without breaking apart. It also stops the liquid from evaporating quickly.
If you don’t have a drop lid, you can make one with aluminium foil. Cut a square out of foil, fold the edges to make it a round shape with the diameter slightly smaller than the pot. Then poke the foil with a knife or a chopstick to make holes in several places.
6. If you are using soybeans which are already cooked, start from Step 3 and add ½ teaspoon of dashi powder.