Preheat the oven to 220C/425F/Gas 7.
Sear the salmon on a hot griddle pan, turning once to lightly brown on each side. Transfer to the oven for three minutes to finish. Remove and set aside.
Place the tomatoes, dressed with a teaspoon of olive oil into a roasting tin and roast for five minutes. Remove from the oven and drain off any juices into a bowl. Place the tomatoes in a warm dish.
Add the juice from the tinned tomatoes, the basil and olive oil to the bowl of roasted tomato juice.
Pour over the roasted tomatoes and serve.