Step 1

Cook pasta according to package directions. Reserve 1 cup of pasta water before draining.

Step 2

Place a large pan over medium heat and add olive oil.

Step 3

Add garlic to the pan and let cook for 30 seconds, stirring constantly so it doesn't burn. Add the crushed red pepper flakes.

Step 4

Pat shrimp dry and add to the pan with the garlic and crushed red pepper flakes. Cook for 1.5 minutes on each side, or until it's no longer translucent. Remove the shrimp from the pan and set aside (if you're omitting the shrimp, skip this step and go directly to step 5).

Step 5

Add the diced red bell pepper to the same pan you cooked the shrimp in. Cook for around 6 minutes, until the peppers are gently seared.

Step 6

Add milk and cream cheese. Stir until cream cheese melts and is combined with the milk. Let simmer until it thickens, about 5 minutes.

Step 7

Add reserved pasta water, salt, pepper, and spinach, and allow the spinach to cook down and sauce to thicken again, another 3-5 minutes. Taste the sauce and adjust the seasonings as necessary (if it tastes bland, add more salt).

Step 8

Add pasta to the pan with the sauce and mix to combine. Add shrimp and serve. Top with freshly grated parmesan cheese if desired.