Bring a large saucepan of lightly salted water to the boil, add the pasta shapes and cook following pack instructions.
Meanwhile, in a frying pan, heat the olive oil, then add the mushrooms. Cook for 5 minutes, until softened and coloured. Add the cherry tomatoes, tuna and tomato pasta sauce, and heat through.
Preheat the grill to a medium-high heat. Add the cooked and drained pasta to the tomato mixture, mix well and transfer to an ovenproof dish.
Tear the mozzarella cheese into pieces and scatter over the pasta. Sprinkle with the dried mixed herbs and chilli flakes, and place under the grill for 5-10 minutes, until the cheese starts to bubble, then serve.
Make it veggie: Try swapping the tuna for 400g roughly chopped leeks. Fry the leeks in the olive oil with the mushrooms at step 2. Complete as above recipe.
Nutrition for veggie option, per portion: 541 cals, 13.7g fat, of which 5.4g saturated fat, 13g added sugar, 1.5g salt.