Preheat the oven to 350 degrees. Line a 9x12 pan with foil so that the edges hang over and spray with cooking spray.
In a medium bowl, cream together the butter, brown sugar, and granulated sugar until light and fluffy.
Add the vanilla, then the eggs, one at a time, and mix well, scraping down the bowl after each addition.
In a small bowl, sift together the flour, baking soda, and salt. Slowly add the flour mixture to the butter mixture.
Fold in the peanut butter chips and chocolate chips.
Spread the batter into the prepared pan and smooth the top.
Bake for 30 minutes, until a toothpick comes out clean (Take care not to overcook these).
Once the blondies have cooled, remove the them by lifting the tinfoil and placing on a cutting board to cut.