In a large skillet, melt butter and oil, over medium heat, add mushrooms, thyme, garlic, salt, pepper and red pepper flakes. Stir occasionally, cooking 10 —12 minutes, until mushrooms are softened and browned. Stir in fresh spinach just until it wilts, about 3 minutes. Remove thyme stems and garlic clove. Spoon some of the mixture onto a warm tortilla and add some salsa.
Keywords: vegetarian tacos, roasted veggie tacos, mushroom spinach tacos