Thai-style beef curry

Ingredients

• 1 tablespoon peanut oil
• 3 brown onions (600g), sliced thickly
• 2 cloves garlic, crushed
• 4 centimetre piece fresh ginger (20g), grated
• 2 fresh long red chillies, chopped finely
• 1 tablespoon finely chopped coriander root and stem mixture
• 1 kilogram gravy beef, cut into 5cm pieces
• 2 cups (500ml) beef stock
• 10 centimetre stick fresh lemon grass (20g), halved lengthways, bruised
• 1 tablespoon tamarind concentrate
• 1 tablespoon grated palm sugar
• 2 x 400ml cans coconut milk
• 1 tablespoon fish sauce
• 800 grams new potatoes, halved
• 1 red capsicum (350g), chopped coarsely
• 2 teaspoons lime juice
• 3 green onions, sliced thinly
• 1 cup (80g) bean sprouts
• 1 fresh long red chilli, sliced thinly
• 1/3 cup loosely packed fresh coriander leaves