Prepare the mushrooms: Shred the king oyster mushrooms lengthwise using two forks to mimic shredded meat texture.
Mix the spice blend: In a small bowl, combine cumin, coriander, smoked paprika, turmeric, cayenne pepper (if using), cinnamon, and cloves.
Marinate the mushrooms: In a large bowl, toss the shredded mushrooms with olive oil, lemon juice, salt, pepper, and the entire spice blend until fully coated. Let this sit for at least 20 minutes.
Cook the mushrooms: Heat a large skillet or cast-iron pan over medium-high heat. Add the marinated mushrooms in a single layer (cook in batches if necessary to avoid steaming). Cook for 5-7 minutes per side until the edges are browned and slightly crispy. This mimics the roasting effect.
Prepare the tahini sauce: Whisk together tahini paste, lemon juice, minced garlic, and salt in a bowl. Slowly add cold water, one tablespoon at a time, whisking constantly until the sauce reaches a smooth, pourable consistency.
Warm the pita bread: Heat the pita bread briefly on a dry skillet or in the oven until soft and pliable.
Assemble the shawarma: Place a portion of the cooked mushroom mixture onto each warm pita. Top with fresh parsley, sliced tomatoes, and pickled red onions. Drizzle generously with the tahini sauce.
Fold and serve immediately.
Notes
Use king oyster mushrooms for the best meaty texture; slice them thinly before shredding for easier handling.
For extra flavor depth, roast the spices lightly in a dry pan for 30 seconds before mixing them into the marinade.
If you prefer a tangier sauce, add a small splash of apple cider vinegar to the tahini mixture.