Heat a tablespoon of oil in a wok or large skillet over medium-high heat.
Add ginger paste and garlic paste, sauté for about 30 seconds until fragrant.
Toss in the diced onion and cook until translucent.
Add the brussel sprouts, broccoli, carrots, bell peppers, and roasted chestnuts. Stir-fry for 3-5 minutes until the vegetables are slightly tender but still crisp.
In a small bowl, mix soy sauce and curry powder to form a paste. Add this paste to the vegetables and stir well to coat.
Pour in the vegetable stock and bring the mixture to a simmer. Let it cook for an additional 3-5 minutes, allowing the flavors to meld and the vegetables to absorb the curry goodness.
Toss in the cashews and stir-fry for an extra 1-2 minutes until everything is well combined.
Season with salt and black pepper powder to taste.
Serve the curry stir fry over rice or noodles for a delicious and satisfying meal!