Neiman Marcus style Chocolate Chip Cookies

yummy treat!
preheat your oven to 350°F
2 & 1/2 cups rolled oats
1 & 3/4 cups all purpose flour
3/4 teaspoon salt
1/2 teaspoon baking powder
1 teaspoon baking soda
1 cup unsalted butter - at room temperature
1 cup granulated white sugar
1 cup brown sugar
2 eggs
2 teaspoon vanilla extract
1 (4 oz) chocolate bar
12 ounce semi-sweet chocolate chips
1 & 1/2 cup chopped walnuts (optional)