Butterflied chilli chicken with sweet potatoes

Ingredients

• Butterflied chilli chicken
• 1.4 kilograms whole chicken
• 2 cloves garlic, crushed
• 1 tablespoon lemon juice
• 3 teaspoons mild paprika
• 1/4 cup finely chopped fresh coriander
• 1/2 teaspoon chilli powder
• 1 tablespoon olive oil
• Sweet potatoes
• 1 medium orange sweet potato, scrubbed and thinly sliced
• 1 medium purple sweet potato, scrubbed and thinly sliced
• 1 medium red-skinned potato (such as pontiac or desiree), thinly sliced
• 2 tablespoons olive oil