Place the dried mushrooms in a heatproof bowl, pour over boiling hot water to cover and leave to soak for 30 minutes until softened. Drain and squeeze out the excess water. Remove and discard the stems, and thinly slice the caps. Trim and then thinly slice the fresh mushrooms.
Spray a nonstick wok or frying pan with cooking spray and heat over a medium-high heat. Add the garlic and chilli paste and stir-fry for a few seconds until aromatic. Add the mushrooms and stir-fry for 2 minutes.
Stir the rice wine into the pan, followed by the stock, soy sauce, sugar and cornflour paste. Season to taste with pepper. Bring to the boil, stirring constantly, then stir in the tofu and spinach. Return to the boil and cook, stirring, for 2–3 minutes until the spinach turns bright green and the mixture has thickened.
Remove the pan from the heat and stir in the sesame oil. Ladle into warmed bowls and serve immediately.