Bring water to a boil, then salt and add the pasta. Stir occasionally to keep the pasta from sticking. At the end of the cooking time, pull out ¼ cup pasta water and set it aside.
Return the pan to the heat and turn on high heat. Add the olive oil. Once it is heated, add the chicken. Sprinkle with about ½ teaspoon of salt and pepper. cook until there is no more pink left.
Reduce the heat to medium and add the minced garlic. Cook for 30 seconds, then sprinkle with flour. Cook this, stirring constantly for about 1 minute. Add in the pasta water, broth, Rotel, basil, and oregano. Mix and cook this for about 2-3 minutes.
Next, add in the half and half, spinach, and parmesan. Mix and cook this for a minute or 2. Taste the pasta and add in more salt and pepper as needed. I wait until the broth and parmesan are added as they are so salty. You don't want to over salt it.
That is it! The dish is done and ready to serve. You can top with more parmesan if you like or serve it like it is!