Preheat the oven to 425°F. Then slice each chicken-breast in half, so it is half as thick as before. The resulting pieces ought to be no thicker than about ½-inch. When damp, pat them dry with paper-towels.
Prepare a baking-dish lined with parchment-paper. Spread-out the chicken pieces in one layer on the parchment-paper.
Season the chicken with half the pepper and salt. Flip them & season the other side together with the remaining pepper and salt. Put aside.
In a pan on the stovetop, cook the spinach till wilted. Separately, microwave cream cheese till very soft and readily blended, for 20minutes.
Then in a bowl, stir together softened cream cheese, cooked spinach and all of other topping ingredients till well-mixed. Evenly spread the mixture across the tops of the chicken bits.
Bake in 425°F till chicken is cooked for 20minutes (depending on how big your chicken pieces). Let it cool at room temperature for 5minutes prior to serving.
Serve and enjoy!