Frozen Pea Soup

Ingredients

• 1 tbsp olive oil
• 1 large leek (white part only, chopped)
• 2 garlic cloves (finely chopped)
• 3 1/2 cups chicken or vegetable stock
• 4 cups frozen peas
• 1 cup fresh mint (chopped)
• 1/2 cup low-fat natural yogurt
• 1 pinch freshly ground pepper
• to serve sumac or paprika