Heat up a large non-stick pan and cook mashed tofu until slightly dry, add 3 tablespoons of oil and continue to stir fry until golden brown. Push the tofu to the side of the pan, then sauté mushrooms and shallots until shallots turn translucent and mushrooms are fully cooked through.
Add garlic and continue to cook for another 30 seconds or until garlic is aromatic.
Season with black pepper, pinch of salt, 5-spice powder, and sugar, then stir to combine.
Add in the soy sauce, cooking wine, water and bring the mixture to a rolling boil.
Continue to cook until the sauce is reduced to almost half. Taste test and season accordingly. If you need more sauce, add a little more water here.
Finally, add the cornstarch slurry to thicken the sauce by stirring constantly over low-medium heat.
Add scallion for toppings and serve warm with rice.