For the garnish
1. You will need six long wooden or metal skewers. If you are using wooden ones, soak them in water for 1 hour beforehand (this stops them from burning).
2. Either preheat the oven to 350°F (180°C) or start heating your barbecue grill. You can also use a grill pan on the stove. Put the seitan into a bowl (squeezing out any excess liquid) and add the tamari. Mix together and leave to marinate for 30 minutes in the fridge. Toss the sweet potatoes in a little vegetable oil and roast in the oven for 20 minutes to soften them slightly before barbecuing.
3. Have all your ingredients handy. You don’t have to be exact, just get a good spread of seitan and vegetables on each kebab, completing each one with a nice fat chili. Place on a large tray or platter, brush well with olive oil and sprinkle with salt and pepper.
4. Make the mango barbecue sauce. Leave 6 tablespoons of the sauce in the food processor and blend until smooth. This will be your marinade for the kebabs. The rest will be your sauce.
5. The key here is to not burn the kebabs on the barbecue (it’s a lot easier to control the temperature in an oven). The heat must be constant, but not blazing. Wait until the flames have died down and there is a white glow to the embers – about 30 minutes. Spread them out a little to form a good base of heat, then place your oiled kebabs on the grill.
6. Barbecue the kebabs for 10 minutes, turning them regularly but not overdoing it. Once they are well colored, begin to brush on your marinade and continue turning and basting for 10 minutes. If using a grill pan, set it on medium and turn the kebabs every few minutes. They should take 15–20 minutes – baste them regularly towards the end of cooking. You can also oven-roast the veggies.
7. Serve the kebabs on some watercress, drizzled with the mango sauce.
Mango Barbecue Sauce
Makes a large bowlful
1. Put the oil into a small pan on medium heat and sauté the onion for 10–12 minutes, until well caramelized. Add the garlic and ginger, cook for 2 minutes more, then add the coriander, paprika and stock and stir. Add the star anise, mango, tamari, tomato paste and molasses. Bring to a boil and cover, then lower the heat and cook for 10 minutes, stir, cook for 10 minutes, stir, cook 10 minutes more, stir. It gets nice and sticky. Taste for sweetness and saltiness – there should be a nice balance of the two.
2. Allow the sauce to cool slightly and remove the star anise. Place in the small bowl of a food processor (or use an immersion blender) and pulse a few times, allowing for some nice chunks of mango. Stir in the lime zest.
Recipe from Peace & Parsnips: Adventurous Vegan Cooking for Everyone: 200 Plant-Based Recipes Bursting with Vitality & Flavor, Inspired by Love & Travel, © Lee Watson, 2016. Reprinted by permission of the publisher, The Experiment. Available wherever books are sold. theexperimentpublishing.com.
"Vegetables are perishable, so we don't have any indication of what they looked like 500 years ago," says James Nienhuis, a professor in the Department of Horticulture at the University of Wisconsin.