Ostrich fillet stir-fry with vegetables and preserved ginger

Ingredients

• 35ml black bean sauce
• 2 garlic cloves, crushed
• 15ml preserved ginger, thinly sliced
• 10ml sesame oil
• 400g ostrich steak, thinly sliced
• 15ml vegetable oil
• 1 small onion, sliced
• 150ml good-quality beef stock
• 100g string beans
• 100g fresh asparagus
• 1 yellow pepper, seeded and finely sliced
• 300g egg noodles, cooked
• sprouts, to garnish