Roasted vegetables are lovely hot or cold, make a great addition to salads and sandwiches, and are easily cooked in large quantities. To save money, make the most of seasonal gluts; depending on the time of year, chop courgettes, aubergines, red peppers, tomatoes and red onions into small chunks, then toss with olive oil, salt, pepper, halved garlic bulbs and any spices you like, before cooking at 180ºC/360°F/gas mark 4 until tender (about 30 minutes). For a more earthy, wintery note, the likes of carrots, parsnips and beetroot work well, too.