Preheat oven to 350 degrees. Line a 9 x 13 baking pan with parchment paper and spray with cooking spray.
Mix the dry ingredients in a large bowl. In a small bowl, mix together the wet ingredients. Pour the wet mixture into the dry and mix well. Pat the mixture into the pan.
Bake for about 15 minutes for chewy granola bars (or a little longer for crunchy granola bars). Remove from the oven and let cool for a couple of minutes then slice into bars. Finish cooling completely before removing from the pan or they will break apart.