Peel the potatoes and cut into thick slices, then strips, then roughly 1 cm cubes. Dice the cucumber into similar-size pieces. Trim and halve the white beech mushrooms.

Soak a handful of dried soy mince in water until it swells. Rinse 2–3 times until the water runs fairly clear, then squeeze out excess moisture firmly.

Heat a generous amount of oil in a wok or pan and add the potato cubes. Let them fry undisturbed for about a minute, then flip; repeat until golden and slightly translucent. Remove and set aside, keeping some oil in the pan.

Add the rehydrated soy mince to the pan and stir-fry until fragrant and lightly browned. Add the beech mushrooms (a touch more oil if dry) and fry until golden at the edges.

Return the potatoes, add the cucumber, then add 1 tsp soy sauce, 1 tbsp vegan oyster sauce and 1 tbsp ketchup. Stir to bloom the seasonings, pour in 60 ml water and toss fast over high heat.

Season with ¼ tsp white pepper and about 1 tsp dark soy sauce for a deep gloss. Toss once more and serve hot over steamed rice. For spice, fold in sliced fresh red chili.