Cook pasta as directed and drain. Return to pot. Stir in spinach, tomatoes and 2 tsp oil. Cover.
In lg skillet, heat 1 tsp oil over medium heat. Add onion, cook 1 min. Add shrimp, garlic and red pepper flakes. Cook, stirring for 2 mins.
Stir into skillet, the broth, or wine plus the other broth, salt and pepper. Cook, until shrimp is pink. Remove from skillet. Stir in parsley and butter until butter is melted. Add whole mix to pasta and toss to mix.