Stir-fry vegetables with cashews

INGREDIENTS

• vegetable oil
• 1 red onion sliced
• 1 red pepper , sliced
• 200g mushrooms , sliced
• 2 heads of pak choi , cut into quarters
• 1 garlic clove , crushed
• 100g cashews
• soy sauce , sesame oil, chilli oil to drizzle (optional)