Nibblous | courgette and tomato "shepherds" pie

Ingredients

• 5 tablespoons olive oil
• 2 onions, sliced
• 1½ lbs (750g) courgettes, sliced
• 2 cloves of garlic, crushed
• 1 tin chopped tomatoes
• 1 tablespoon tomato puree
• 750g potatoes, boiled and mashed
• 4 spring onions, finely chopped
• 4 tablesppons milk
• Salt and pepper
• Cheese for topping if you like - I do!