In a medium shallow bowl, combine flour with paprika, Italian herbs, dried basil, salt, and pepper. Whisk together.
Tenderize the breasts with a mallet to flatten a bit.
Dredge the chicken breasts in the flour mixture and tap off any excess.
Place a large pan over medium-high heat and add 3 tablespoons of butter. Once melted add the chicken breasts and cook until golden brown on each side, about 3-5 minutes per side.
Cover the chicken and reduce the heat to medium and cook until it reaches an internal temperature of 165 degrees F or 75 degrees C. Remove and set aside, cover with foil to keep it warm.
Add remaining 3 tablespoons of butter, 1/2 of the diced onion, 1/2 of the minced garlic, salt, and pepper to taste. Cook and stir frequently until the onion is translucent. Then add the spinach, stir and cook for a few minutes, just until wilted.
In a saucepan, add the butter and melt it, add the rest of the onion and cook until translucent over medium heat. Add the garlic and stir frequently, cook for 1 minute.
Add the wine, stir, and cook until reduced.
Add the milk, cream, stir, and add the gouda. Stir until combined and smooth.
Add a good amount of spinach to a plate, drizzle some sauce on top and add the chicken, spoon more sauce on top of the chicken and garnish with parsley.