Preheat the oven to fan 180C/conventional 200C/gas 6. Spread the tomatoes out on a large baking tray and prick each one with a fork. Sprinkle with olive oil, sea salt and freshly ground black pepper and scatter with the garlic. Roast in the oven for 15 minutes.
Lay asparagus flat in a large frying pan over a medium heat. Splash with 3 tbsp olive oil, sprinkle with sea salt and freshly ground black pepper. Roll the spears until they’re hot and evenly coated with oil.
Remove tomatoes from oven and pour off the excess juice. Push tomatoes to one side of tray and lay asparagus next to them. Return to oven and roast for 15 minutes. Sprinkle with the olives before serving warm or at room temperature. Vegetables can be done up to two hours before serving and kept at room temperature.