Preheat oven to 220°C (or 200°Cfan bake).
Make chipotle-pineapple sauce: In a nutribullet or food processor, blitz garlic, soy sauce, chipotle sauce, smoked paprika and the first measure of pineapple together, until completely smooth. Set aside.
Cook mushrooms: Tear mushrooms into chunks, roughly 3cm. Toss mushrooms and onion on a large roasting tray with the chipotle-pineapple sauce, until well coated. Drizzle with olive oil and season lightly with salt and pepper. Roast for about 20-25minutes, until tender and sauce has reduced. Toss once during cooking.
Meanwhile, make charred pineapple salsa: Heat a drizzle of oil in a large fry-pan on high heat. Cook the second measure of pineapple and cumin seeds for 5-6 minutes, tossing occasionally, until lightly charred. Transfer to a bowl and add the remaining salsa ingredients and a pinch of salt. Toss together and set aside to serve.
Warm tortillas: Wrap tortillas in foil and warm in oven for 10 minutes.
Serve tortillas filled with vegan sour cream or yoghurt, mushrooms, salsa, radish and coriander. Serve lime wedges on the side for squeezing.