Cook chicken breast fillets (or your choice of chicken) according to package directions.
While the chicken is cooking, prepare the rest of the sliders by cutting the rolls in half horizontally and placing the bottom in a greased 9x13” baking dish. 18 rolls will fit snugly.
In a small bowl, mix together mayonnaise, mustard, garlic powder and worcestershire sauce, and spread it over the bottom half of the rolls.
Add the prepared, cooked fillets in a single layer on the rolls (my package of chicken had 6 fillets, and they fit almost exactly in one layer across all 18 sliders).
Top the chicken with ham slices, then layer on the sliced swiss cheese.
Place the top half of the rolls over top, then brush with melted butter.
Adjust the oven temperature to 350℉. Bake for 15-20 minutes, or until the tops of the rolls are golden brown and cheese is melted.
Remove the sliders from the oven, garnish with chopped parsley (if desired), cut into individual sandwiches and serve.
Notes
Freeze the sliders by wrapping them tightly in plastic wrap and placing them in a gallon-size freezer bag or freezer-safe container for up to 2 months. Cook them from frozen by making sure to remove any plastic wrap, covering with foil, and bake for 20-25 minutes at 350℉ until heated through.