Preheat oven to 200°C fan / 430°F. Place all of the chopped ratatouille vegetables and garlic in a baking tray measuring 30 x 22 x 5cm / 12 x 8 x 2″. Drizzle over the olive oil, sprinkle with salt and pepper; toss to combine.
Place in the preheated oven and bake for 25 minutes until the vegetables are tender.
Remove from the oven and add the chopped tomatoes. Fill the empty chopped tomatoes tin with water and pour this into the dish. Stir in the spinach, orzo, miso, tahini and 1 teaspoon of fine salt, making sure that the miso and tahini are evenly distributed. Return everything to the oven for a further 20 minutes.
Remove from the oven and stir through the fresh spinach. Pour over the fresh lemon juice and top with the fresh basil and red chilli flakes (if using), before serving.