I have been making these bar for years.  I do not know where this recipe originates from I found it online, and I love it!

Preheat oven to  350 degrees. Crust:  1 (15.25 oz. ) box butter cake mix, 1 stick unsalted butter, melted, 1 egg, 1 cup finely chopped pecans.  In a bowl dump cake mix, butter, egg, and pecans, mix well.  Pour this mixture into a 13 x 9 inches casserole dish.  With your hand press down to the bottom of the pan. Filling: 2 (8 oz.) packages cream cheese, 3 eggs, 2 cups powdered sugar, 2 teaspoons vanilla extract. In a bowl add the cream cheese, beat with a hand mixer until smooth, add vanilla and eggs one at a time, beat after each addition, add sugar and mix well. Pour this mixture over the cake mix crust.  Bake for 30-35 minutes. Remove from the oven, allow to cool cut into bars and serve.

Do you have a favorite bar cookie?  If you have a favorite, please share your recipe with the rest of us.