Pre-heat the oven to gas mark 7 (230°C for fan-assisted or 450°F) and pop the kettle on to boil. Peel the skin off the chorizo and cut into rounds about 1/2cm wide. Chop the graffiti aubergines into small cubes around 1cm thick, slice the sweet pointed peppers into rounds about 1/2cm thick. Chop the red onion in half, peel and chop into large chucks around 2cm thick. The idea is to have slightly varying sizes for added texture, so don't feel you need to be exact here.
Add the chorizo to an oven-friendly pan, a cast iron shallow casserole dish works really well, and dry fry on the hob using medium-heat. Stir occasionally until the oils are released, this usually takes around 2-3 minutes. Then add the graffiti aubergines, sweet pointed peppers, onions and stir to coat in the chorizo oil. Add the tomatoes, still on the vine and transfer dish to the oven. Roast for 10 minutes.
Meanwhile mince the garlic and make up 1 pint (568ml) of chicken stock, set to one side. After the chorizo and vegetables have roasted for 10 minutes, take the dish out of the oven and place back on the hob using a low-heat. Turn the oven down to gas mark 5 (190°C for fan-assisted or 375°F).
Remove the tomatoes from the dish so you can give everything a good stir. Add the minced garlic, orzo and the red pesto. Let the orzo soak up the cooking oils and pesto for a moment, then add the stock. Place the tomatoes back on top. Put the dish back into the oven, covered with a lid and cook for 8 minutes.
After 8 minutes, take the dish out of the oven and fluff the orzo up with a fork (be sure to scrape the bottom of the pan to really mix everything). Stir through half a tablespoon of extra virgin olive and add back to the oven for a further 5 minutes un-covered.
After the final 5 minutes check the orzo is cooked to your liking, (slightly al dente works best). If it needs a couple more minutes or is looking too dry add a splash of water (no more than 3 tablespoons) and place back in the oven un-covered until ready.
To serve, give the orzo a final fork through and scatter fresh thyme and purple basil leaves over the top for a fresh finish. Season with salt and pepper to taste.