Chicken Cordon Bleu

4 lag. Chicken breasts (again, look for the thinly cut breasts... makes for a lot less work!)
1 T. Dijon mustard (optional... my kids prefer it without)
1/2 tsp. thyme
4 slices cooked ham
2 slices Swiss
1/4 c. seasoned bread crumbs
1 T. grated Parmesan
4 tsp. melted margarine (1 beaten egg mixed with some milk also works well
Preheat oven to 400 degrees
Pound chicken to 1/4 inch thickness between two pieces wax paper. Spread mustard evenly down center and sprinkle with thyme. Top with ham slice and half a slice cheese. Roll up jelly roll style, tucking in sides of chicken to secure. Secure with toothpicks.
Combine bread crumbs and Parmesan. Brush each chicken roll with melted butter and roll in crumb mixture. Bake at 400 for 10 minutes then reduce oven temp. to 350 degrees and bake 20-25 minutes, until chicken is tender