In a mixing bowl, combine all-purpose flour, baking powder, dried parsley, salt, and ground black pepper. Incorporate cold vegan butter until the mixture resembles coarse crumbs. Gradually add soy milk, mixing until a shaggy dough forms. Cover and refrigerate for at least 30 minutes.

While the dumpling dough chills, prepare your vegetables. Finely dice the onion, carrots, and celery, and slice the mushrooms thinly. Mince the garlic.

Heat a large pot over medium heat and pour in olive oil. Once hot, add the diced onion and minced garlic, sautéing for about 2-3 minutes until fragrant. Next, stir in the carrots, celery, and mushrooms, cooking for an additional 8-10 minutes.

Stir in tomato paste, vegan Worcestershire sauce, and a sprinkle of dried parsley, then pour in vegetable broth and add cannellini beans. Bring to a gentle simmer for about 5 minutes.

Form the chilled dumpling dough into 9-10 equal balls. Drop into the simmering stew, cover, and cook for 10 minutes. Uncover and ladle broth over the dumplings, sprinkle fresh thyme, and continue cooking for another 3-5 minutes.

Once the dumplings are fluffy, remove from heat. Ladle into bowls and serve hot.