1. Fill a large pot with lightly salted water and bring to a rolling boil. Cook fettuccine at a boil until tender yet firm to the bite, about 8 minutes; drain pasta. 2. Meanwhile, pour cream into a large skillet. Cook over medium heat, stirring constantly, until just about boiling. Reduce heat and add green onions, parsley, basil, thyme, salt, black pepper, red pepper flakes, and white pepper. Simmer until thickened, 7 to 8 minutes. 3. Stir in shrimp and scallops. Cook until shrimp is no longer translucent. 4. Stir in cheeses, blending well. 5. Serve sauce over pasta. 6. Serve hot and enjoy!