Boil pasta until slightly al dente, be sure not to cook the pasta all the way or it will fall apart later. Reserve one cup of pasta water for the sauce.
Sauté the garlic and shallots with the butter in a skillet for 2 minutes over medium heat or until fragrant.
Add shrimp and salt to skillet, cooking shrimp for 3-4 more minutes, until pink and cooked through.
Add pasta to skillet, tossing well. Add pasta water 1-2 tablespoons at a time, tossing until absorbed.
Add parsley, lemon juice, zest and red pepper, tossing. Remove from heat, add cream and Parmigiano, tossing to create creamy sauce. Add additional pasta water as needed to thin sauce until desired consistency is reached. Add salt to taste.
Serve immediately topped with additional Parmigiano and red pepper if you want!