Heat butter in a pan. Add finely chopped garlic and sauté for a few seconds.
Add oyster mushrooms, salt, pepper, chili flakes, and oregano. Cook until mushrooms shrink and release water.
Add thinly sliced onion and yellow bell pepper. Cook until all moisture is absorbed. Transfer to a plate.
In the same pan, roast peanuts until slightly browned.
In a mixing bowl, combine roasted peanuts, cooked mushroom mixture, grated or thinly sliced carrot, purple cabbage, chopped lettuce, and spring onions. Mix gently.
For the dressing: Combine soy sauce, vinegar, sesame seeds, brown sugar, pepper powder, coconut oil, and water in a small jar. Shake well to mix.
Transfer the salad to a serving bowl, garnish with pomegranate seeds, and drizzle the dressing just before serving.