Preheat the oven to 350 degrees F. In a large bowl, mix together the flour, graham cracker crumbs, brown sugar, baking soda, and butter. Set aside 1-½ cups of the crumb mixture and pat the rest into an ungreased 9x13-inch baking dish. Place the cheese slices on top of the crumb mixture.
In a medium-size bowl, combine the apples and granulated sugar. Layer over the cheese. Add the nuts to the reserved crumb mixture and sprinkle over the apples. Bake for 35 to 40 minutes, or until golden brown. Cool completely, then cut into 2-inch squares. This can be served as a side dish with bean soup or as a dessert.