Winter vegetable & lentil soup

Name: Winter vegetable & lentil soup
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Cuisine: European, British
Ingredients: 85g dried red lentils; 2 carrots quartered lengthways then diced; 3 sticks celery sliced; 2 small leeks sliced; 2 tbsp tomato purée; 1 tbsp fresh thyme leaves; 3 large garlic cloves chopped; 1 tbsp vegetable bouillon powder; 1 heaped tsp ground coriander