In a small bowl, combine 2 cups of boiling water with the shitake mushrooms, and let them soak, uncovered for 30 minutes. Drain the liquid into a medium-sized saucepan and discard the mushrooms. Bring the broth to a simmer and cover.
In a small bowl, toss the spinach, lemon juice and 1 teaspoon of the salt. Set aside.
Heat 1 tbsp olive oil in a saucepan over medium heat. Sauté the chopped garlic and onions until onions are translucent. Add the mushrooms and thyme and cook for 4 minutes until mushrooms are soft. Stir in the dry rice along with 1 tbsp of olive oil. Stir the dry rice constantly for about 4 minutes until fully coated with the oil. Add wine and stir constantly until all the liquid is absorbed.
Ladle ¾ cup of the simmering broth into the rice and cook, continuing to stir, until most of the liquid is absorbed. Add another 3/4 cup of broth and let it absorb into the rice. Continue doing this until the rice is of a creamy consistency, about 20 minutes.
Add the spinach and cook for just about 2-3 minutes, stirring constantly, or until the spinach is wilted and bright green. Stir in the dairy-free soy margarine and nutritional yeast. Add salt and pepper to taste and serve immediately.