Lentil Shepherds Pie

Name: Lentil Shepherds Pie
Ingredients: 1 cup of uncooked brown lentils, rinsed; 1 onion, finely chopped; 2 cloves of garlic, crushed; 2 carrots, finely chopped; 1 courgette (zucchini) finely chopped; 1/2 cup of frozen peas; 1/2 cup of frozen sweetcorn; sprinkling of thyme; 1 teaspoon of paprika; balsamic vinegar; 2 bay leaves; 3 cups (720ml) of low sodium vegetable stock; 2 heaped tablespoons of tomato paste; black pepper to season; 2 large sweet potatoes, peeled and chopped; 100g of cheddar cheese; 1 tablespoon of olive oil