Cook bacon to fully done. Drain on towel lined plate. Wash chicken and pat dry. If using whole chicken breasts, butterfly and pound them evenly first. If using cutlets, leave them as they are. Spread cutlets on cutting board. Season with salt and pepper to taste. Line one half of cutlet with approximately 6-8 baby spinach leaves (overlapping). Place 1 piece of bacon and 1 ounce of Swiss cheese on top of spinach. Lift un-stuffed side to meet the edges of the stuffed side and secure with two to three toothpicks placed along the seam. Lay chicken on its side on a baking sheet lined with aluminum foil or parchment paper. Season with a little more sea salt and pepper if desired. Bake in a 350ºF oven for 30 minutes or until no longer pink. Remove toothpicks and enjoy!