Spinach and Feta Pasta with Shrimp

1. Bring a large pot of lightly salted water to a boil. Cook pasta in boiling water until al dente. Drain. 2. Heat olive oil in a large skillet over medium-high heat. Add onion, garlic and mushrooms, cook until soft. 3. Drain juice from tomatoes and add them to the skillet along with the shrimp, spinach, pepper and crushed red pepper. Cook until spinach is wilted and any juices are mostly gone, about 5 minutes. 4. Reduce heat to medium, stir in pasta and feta and cook until cheese is melted. 5. Note: shrimp can be substituted with chicken or omitted for a vegetarian meal.