Brian Turner vegetable casserole with potatoes and red peppers recipe on Christmas Kitchen with James Martin

Brian Turner cooks vegetable casserole with leftover potatoes, red peppers and onions for the festive season on Christmas Kitchen with James Martin.

Brain says: “This hearty vegetarian casserole is quick, easy and cheap as chips to make – plus, it’s handy for using up leftovers.”

The ingredients for the casserole are: 4 tbsp rapeseed oil, 2 carrots, chopped, 2 celery stalks, chopped, 500g roasted chicken bones (optional), 1 garlic bulb, crushed slightly with a rolling pin, 100g tomatoes, chopped, 2 sprigs fresh thyme, 2 tbsp chopped parsley stalks, 3 large onions, chopped, 2 tbsp chopped fresh coriander, 3 large red peppers, thinly sliced, 6-8 leftover roast potatoes, thickly sliced, 50g butter, melted, salt and freshly ground black pepper.

For the mushrooms: 1 tbsp oil, 1 garlic clove, sliced, 340g Portobello mushrooms, sliced and 2 tbsp chopped fresh coriander.