Pat chicken breast (4) dry with paper towels to remove any moisture. Season chicken with salt and pepper.
Mix together the flour (2 tablespoons) and 2 tablespoons of Parmesan cheese in a shallow bowl or plate. Dredge chicken breasts in flour mixture, shaking off excess.
Heat olive oil (4 tablespoons) in a large skillet until it begins to shimmer. Brown the chicken on both sides, over medium heat, and continue to cook until the chicken is cooked through Remove the chicken to the plate and loosely cover with aluminum foil to keep it warm.
Add 2 tablespoons of butter and the garlic (1 tablespoon) to the same skillet and saute on low heat, until the garlic is fragrant.
Add the chicken broth (1/2 cup) to the skillet and bring to a boil over medium heat, stirring well to loosen all the brown bits on the bottom of the pan. Reduce the heat and simmer uncovered, until the broth is reduced to about 1/4 of a cup.
Stir in heavy cream (1 1/2 cups), parmesan (1/2 cup), sun-dried tomatoes (1/2 cup), spinach (1 cup), 1/2 teaspoon salt, 1/2 teaspoon black pepper, and Italian seasoning (2 teaspoons).
Add chicken back into the sauce and flip it over once to coat. Serve.
Notes
Cooking the chicken thoroughly: A good thermometer can be of use here. The thickest part of the breast should reach 165ºF (74ºC). (Remove from heat at 160 for best results, then check to make sure that you’ve got the extra five degrees after letting it sit for a couple of minutes.)
If you don’t have or don’t like using a thermometer, there are a few other tricks to try. The chicken shouldn’t jiggle when you shake it, and the juice should run clear (instead of pink) when you make a small cut. Another good rule of thumb is five minutes per side when cooking on the stovetop.