Start by preparing the marinade for the portobello mushrooms. In a mixing bowl, whisk together the balsamic vinegar, olive oil, light miso, minced garlic, grainy mustard, sea salt, and black pepper.
Remove the stems from the portobello mushrooms and gently wipe them clean with a damp cloth. Place the mushrooms in the marinade, ensuring they are thoroughly coated. Let them marinate for at least 15-30 minutes to absorb all that flavor.
While the mushrooms are marinating, prepare the dressing. In a blender, combine the soaked cashews, garlic, lemon juice, capers, grainy mustard, coconut aminos or tamari, sea salt, and black pepper. Add 1/2 cup of water and blend until smooth. Adjust the consistency with more water if necessary; it should be creamy but pourable.
Preheat your grill or grill pan over medium heat. Once hot, add the marinated portobello mushrooms, gill side down. Grill for about 5-7 minutes on each side, or until they are tender and have nice grill marks.
In a large bowl, add the chopped lacinato kale. Drizzle a bit of olive oil, sprinkle some sea salt, and massage the kale for a few minutes until it softens. This step enhances the kale’s texture and flavor, making it less bitter.
To assemble your pitas, take a warm whole wheat pita and stuff it with a generous amount of the massaged kale. Slice the grilled portobello mushrooms and layer them on top. Drizzle with the creamy kale Caesar dressing and top with sliced tomatoes if desired.