• Chop the vegetables.

For the tempura:

• In a large bowl, whisk the egg with salt and water, then add the flour, starch, and baking soda, stirring rapidly. You could use chopsticks for this. Do not mix for too long or you risk the mixture becoming rubbery. Don't worry if lumps remain as this is normal with tempura.

For the sauce:

• Finely chop the chili and green onion, mix them together with the grated ginger, and the rest of the ingredients.
• In a wok, heat the frying oil over medium-high heat.
• Coat the vegetables with the tempura mixture, draining off the excess, and deep fry in small batches. Avoid crowding the wok.