Bring a large pot of salted water to a boil. Cook pasta to al dente according to package directions. Reserve 1 cup of pasta water before draining.

In a large skillet, heat 1 tbsp butter and 1 tbsp oil over medium-high heat. Add sliced mushrooms and sauté until golden brown (5-6 mins). Remove to a plate.

Add another tbsp of oil to the skillet. Season shrimp with salt and pepper, then sear for 1-2 minutes per side until pink. Remove to the plate with mushrooms.

Reduce heat to medium. Melt remaining butter in the skillet. Add minced garlic and red pepper flakes; sauté for 1 minute until fragrant.

Deglaze pan with white wine (or broth), scraping up brown bits. Simmer for 2 minutes.

Add drained pasta, 1/2 cup reserved pasta water, mushrooms, and shrimp to the skillet. Toss vigorously until sauce emulsifies and coats the noodles.

Stir in lemon juice and fresh parsley. Serve immediately.