Super greens soup

Ingredients

• 1 teaspoon olive oil
• 2 leeks, finely sliced
• 1 medium potato, peeled and finely chopped
• 2 cloves garlic, finely diced
• 1 large head broccoli, about 300g, roughly chopped
• 250g frozen peas
• 500ml reduced-salt vegetable stock
• 100g spinach
• Large handful of fresh coriander, roughly chopped
• Freshly ground black pepper