Bring 4 quarts of water to a rolling boil, add pasta nest and cook until internal temperature reaches 165˚F or approx. 1½ minutes.
Drain pasta, reserving ½ cup of pasta water. Set both aside.
In a medium sauté pan, sear shrimp on both sides and cook until pink.
Remove from pan and set aside.
In the same pan heat 1 Tbsp oil and sauté garlic until fragrant, being careful not to burn.
To the pan add ricotta, heavy cream, lemon juice, lemon zest, crushed red pepper and the reserved pasta water.
Cook on low-medium heat until the ricotta melts and the sauce starts to heat and come together.
Once sauce starts to simmer, add the spinach, shrimp and fold in pasta.
Garnish with additional lemon and Parmesan cheese.