·2 tbsp olive oil ·2 onions, peeled, quartered and thinly sliced ·2 garlic cloves, peeled and chopped ·3 courgettes, about 450g, cut into 5mm slices ·ground black pepper ·300g ripe plum tomatoes cut into 5mm slices ·3 stems tarragon, leaves stripped and roughly chopped ·50g breadcrumbs ·110g half fat hard cheese, finely grated
This gratin dish can be made up to the end of step 4 several hours ahead of cooking. 1. Preheat the oven to 200°C (400°F) mark 6. Warm 1 tbsp olive oil in a large frying pan and add the onion and garlic and 2 tbsp water, and cook, stirring for 5 minutes or until softened. 2. Remove the onions to an ovenproof dish or gratin dish and spread them evenly over the base. Season with pepper. 3. Warm the remaining oil in the same pan, raise the heat to medium high and add the courgette. Cook, stirring occasionally, until they start to colour, about 5 minutes. Tip the cooked courgettes out of the pan so they cover the onions and garlic in the dish. 4. Scatter the courgettes with the tarragon leaves then tuck in the tomato slices randomly between the courgettes. Mix together the breadcrumbs and grated half fat hard cheese and sprinkle over the vegetables. 5. Cover with foil and bake for 20 minutes. Remove the foil and continue to bake for another 10 minutes to brown the top. Serve immediately.