Cook whole wheat pasta according to package. Reserve 1 cup of pasta water and set aside. Drain pasta and toss with 1 tsp olive oil. Set aside.
In a skillet over medium heat, add olive oil. Once olive oil is hot, add mushrooms. Sauté for 2-3 minutes. Add garlic, rosemary, thyme, salt and pepper to taste. Sauté for 4-5 minutes.
Add cooked whole wheat pasta, nutritional yeast, and 3/4 cup of the pasta water. Toss until well coated.
Add spinach and stir until it wilts. Add more pasta water if it is dry. Serve while hot.