In a bowl, combine the flour, cinnamon, baking powder, baking soda and salt. Set aside.
In another bowl, beat together the eggs, sugar, oil and pumpkin.
Gradually add the dry ingredients to the pumpkin mixture and mix well.
Pour into a greased 10x15x1 baking pan.
Bake for 25-30 minutes.
Make the Frosting:
In a bowl, use a hand mixer to cream together the cream cheese and butter. Add the sugar, vanilla and milk. Mix until smooth.
Spread frosting over cooled bars.
Sprinkle with chopped pecans if desired.
Store in an airtight container in the refrigerator. Remove the bars 2 hours before serving if you don't want them cold.
The calories shown are based on the cake being cut into 24 pieces, with 1 serving being 1 pumpkin bars. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**