Easy, budget friendly batch chicken soup

Ingredients

• 2 tsp olive oil
• 1 onion, chopped
• 2 garlic cloves, crushed
• 3 leeks, sliced
• 400g chicken fillets or leftovers
• 1ltr chicken stock (homemade or stock cube)
• 3 carrots, chopped
• 2 potatoes, peeled and chopped
• 1 tsp mixed herbs, dried
• 1 tsp black pepper