Slow cooker lamb shanks

Ingredients

• 2 tablespoon olive oil
• 4 (1kg) French-trimmed lamb shanks
• 1/2 cup (75g) plain flour
• 2 medium (300g) brown onions, chopped
• 2 medium (240g) carrots, chopped
• 4 clove garlic, crushed
• 2 tablespoons tomato paste
• 1 cup (250ml) red wine
• 2 cup (500ml) salt-reduced beef stock
• 2 400g cans chopped tomatoes
• 2 tablespoon sugar
• 1 bouquet garni (see notes)