In a small saucepan, heat vegetable broth over medium heat to keep warm.
In the meantime, heat a large saucepan over medium heat. Add olive oil and mushrooms. Sauté until tender and slightly browned. Remove from pan and set aside in a small dish.
Heat the same large saucepan over medium heat once more.
Add olive oil and onions fry for one minute. Add arborio rice and cook for another minute, stirring occasionally to coat.
Add dry white wine and stir gently. Cook until the liquid is absorbed.
Continue to add vegetable stock, stirring to incorporate, until the rice is 'al dente' - cooked through but still has a slight bite.
Once the rice is cooked through and al dente, remove from heat add vegan butter, vegan parmesan cheese, spinach and the cooked mushrooms. Stir to coat.