Easy cottage pie

• 1 tbsp olive oil
• 1 onion (chopped, or use frozen chopped onion)
• 500 g beef mince (or brown or green lentils for a meat-free version)
• 300 g frozen diced vegetables
• 1 tbsp tomato puree
• 1 × 400g tin chopped tomatoes
• 1 beef or vegetable stock cube
• 300 ml water
• 900 g potatoes (peeled and cut into chunks)
• butter and a splash of milk (optional, for the mash)
• salt and pepper

Method

1. 1Put the potato chunks in a large pan of water, bring to the boil and cook for 15 to 18 minutes until tender.
2. 2Meanwhile, heat the oil in another large pan over a medium heat. Add the onion and cook for 4 to 5 minutes until softened.
3. 3Add the beef mince (or lentils) and cook, breaking up the mince with a spoon, until browned.
4. 4Stir in the tomato puree, chopped tomatoes, frozen vegetables, crumbled stock cube and water.
5. 5Bring to a simmer, then cook for 15 minutes until thickened. Season to taste. If using lentils, check they are tender and add a little more water if needed.
6. 6Drain the potatoes and mash until smooth, adding a little butter and milk if you like. Season to taste.
7. 7Spoon the mince into an ovenproof dish, top with the mash and spread it out. Grill or bake at 200C (fan 180C) for around 20 minutes until golden on top.