Cook pasta as directed on package. Drain well. Set aside.
Meanwhile, melt butter in large skillet on medium-high heat. Add garlic; cook and stir 30 seconds. Stir in cream, marjoram, rosemary and crushed red pepper. Bring to simmer.
Stir in shrimp and Parmesan cheese; cook 3 minutes or until cheese is melted and shrimp are just pink, stirring occasionally. Add pasta; toss to coat well. Sprinkle with parsley and additional shredded Parmesan before serving, if desired.