Preheat oven 375°. Heat a couple of tablespoons olive oil in a Dutch oven or heavy stock pot over medium heat. Crumble up some cooked bacon and a half of a chopped onion, add it to the pot. Place a bunch of washed and trimmed kale leaves in the pot. Cook, covered, stirring occasionally until leaves are wilted and onions cooked through. Set aside.
Pound out 4 skinless, boneless chicken thighs (I had to de-bone & de-skin mine) to approx. 1/2 inch thickness OR 4 skinless, boneless chicken breasts pounded out. Add your choice of cheese to the kale mixture, approx. 1/2 C. I chose Feta. Place several tablespoons of kale mixture onto each chicken piece then roll up tightly. Either tie tightly with kitchen string or hold with a toothpick.
Place in lightly greased baking pan. Sprinkle with salt and pepper. Cook at 375° for 35 minutes then increase heat to 500° or under broiler for 5-10 minutes to brown.