Put the farro into a small bowl and cover with cold water. After 2 minutes, drain and rinse under cold water. Put a small saucepan over medium heat and add farro, along with 1 1/2 cups of water and 1/2 teaspoon salt. Bring to a boil and reduce heat. Cook covered and undisturbed, for 15 to 20 minutes or until all water is absorbed. Turn off the heat and allow the farro to sit for another 10 minutes with the cover on.
In small saucepan bring 4 cups of water to a boil. With a damp paper towel, clean mushrooms of any dirt. Cut mushroom stems into 1-inch thick medallions, or ‘scallops.” Put them into a medium bowl and pour the hot water over; cover with a clean paper towel, and soak for 10 minutes.
Rinse and dry the fresh produce. Peel, halve, and thinly slice the onion. Trim and thinly slice celery, creating half-moon shapes. Peel and mince the ginger. Mince 1 clove of garlic. Pick the cilantro leaves from the stems and reserve for garnish. Cut cherry tomatoes in half and reserve for garnish.
Put a medium skillet over medium-high heat and add the vegan butter. Add half of the soy sauce, reserving 1 tablespoon for step 6, and the sugar and cook until slightly reduced, about a minute. Add “scallops” to skillet, turning and browning on both sides for about 5 to 7 minutes.
Heat 1 tablespoon oil in a large skillet or wok over high heat. Add red pepper flakes and broccolini, shaking the pan frequently until it is bright green and tender, about 3 to 5 minutes. Season with salt and transfer to a plate. Add 1 tablespoon of oil to the skillet. Add the onions and cook until lightly browned in places, 3 or 4 minutes. Add the cabbage, celery, garlic, and ginger. Stir-fry the vegetables until they are tender, about 2 to 3 minutes.
Add cooked farro to the skillet or wok along with the remaining tablespoon of soy sauce and the sesame oil. Stir-fry until farro begins to sizzle and pop, about 5 minutes. Taste and adjust seasoning with salt and pepper. To serve, place “scallops” on a bed of the farro and garnish with cilantro leaves and tomatoes. Serve broccolini on the side.