Method

1. Preheat your oven to grill.
2. Peel and quarter your onions and spread out on a lined baking tray. Lightly crush your garlic cloves but leave the skin on and place on the baking tray. Drizzle with one tbs of sunflower oil. Add oregano, cumin, cinnamon and paprika and grill for 10 - 12 minutes or until lightly charred, then set aside to cool.
3. Place 1 tbs of sunflower oil and mushrooms on a lined baking tray and bake at 180°C for 30 minutes. Remove and shred with forks.
4. Once the onions and garlic are cooled, remove the peel from the garlic clove and discard. Add the onions and garlic to a food processor or blender along with the spices from the tray. Add the tomato paste, apple cider vinegar, Marmite and warm water. Blend until smooth.
5. Pour the mixture into a saucepan and bring to the boil. Once boiling, reduce to a simmer until ready to serve.
6. Preheat a fry pan on a medium heat. To make the tacos, dip the tortillas in the Marmite broth and place in the pan to fry. Top with grated cheese and shredded mushrooms and cook until the tortilla is golden and crispy on the bottom and the cheese is melted. Fold in half and transfer to a plate. Repeat with the remaining 5 tortillas.
7. To serve, top the tacos with finely diced red onion and coriander and serve with a side of Marmite broth for dipping and lime wedges.