Rehydrate the dry soya chunks in boiling water for 10 minutes until softened, then drain and squeeze out all excess moisture thoroughly.
Place the damp soya chunks in a bowl and toss with cornstarch, sea salt, and black pepper until every piece is evenly coated.
Heat the avocado oil in a large non-stick skillet over medium-high heat and sear the soya chunks until they are golden brown and crispy on all sides.
Add the sliced bell peppers and red onion to the skillet, stir-frying for 3-4 minutes until the vegetables are tender-crisp.
In a small bowl, whisk together the minced garlic, grated ginger, tamari, gochujang, and rice vinegar to create the sauce.
Pour the sauce mixture into the skillet and toss everything together for 1-2 minutes until the glaze thickens and coats the chunks beautifully.
Remove from heat, drizzle with sesame oil, and garnish with freshly sliced green onions before serving.