Spiced Tomato Dahl

Name: Spiced Tomato Dahl
Ingredients: 1 tablespoon olive or sunflower oil; 1 teaspoon coriander seeds; 1 teaspoon cumin seeds; 1 teaspoon turmeric; 1 onion, peeled and diced; 2 garlic cloves, finely chopped; 1 chilli, finely chopped; 500 g fresh tomatoes, diced; 1 small piece of ginger, peeled and grated; 175 g red lentils; 1 stock cube; 1 spring onion, finely chopped; salt and freshly ground black pepper; salt and freshly ground black pepper; 1 tablespoon olive or sunflower oil