1Cook and drain spaghetti as directed on package.
2Meanwhile, in large skillet, melt 1 tablespoon of the butter over medium heat. Cook garlic and pepper flakes in butter 1 minute, stirring constantly. Add mushrooms; cook 3 to 4 minutes, stirring occasionally, until lightly browned. Stir in shrimp; cook about 4 minutes, stirring occasionally, until shrimp are almost pink. Add wine and remaining 2 tablespoons butter; heat to simmering.
3Add cooked spaghetti to skillet; toss with shrimp mixture. Season with salt. Cook 1 minute longer until shrimp are pink. Sprinkle with parsley.