Heat a little oil in a large skillet over medium heat. Add the onion and sauté until softened.
Add the mushrooms and cook until tender and most of the liquid has evaporated.
Add the garlic, balsamic vinegar, soy sauce, smoked paprika, ground coriander, and black pepper. Cook for another 1-2 minutes.
Stir in the spinach and cook just until wilted. Remove from the heat.
Mix the cornstarch with a splash of the plant milk in a small saucepan until smooth.
Add the remaining plant milk, neutral oil, nutritional yeast, garlic powder, smoked paprika, and salt. Whisk until combined.
Cook over medium heat, stirring constantly. Once the sauce begins to bubble, continue cooking for about 3 minutes, until thick and creamy.
Spread the cheese sauce over each tortilla. Add the mushroom filling and fold the tortillas in half.
Toast in a skillet over medium heat until golden and crisp on both sides.
Slice and enjoy warm.
