Blueberry Oatmeal Bars

I have been on a bit of a baking kick lately, adding pureed vegetables to baked goods.  This was one wonderful recipe.  I actually read comments online and decided to make these in a 13"x9" so that we had thinner, crispier bars.  I also used frozen blueberries instead of preserves.  We shared them at a dinner party and they were a hit.

* image from The Ginger Snap Girl

Blueberry Oatmeal Bars
Nonstick cooking spray 
2 cups old-fashioned oats
1 1/4 cups all-purpose flour
1/2 cup sugar 

1/2 tsp. cinnamon
1/4 tsp. baking powder
1/4 tsp. salt
1 tsp. pure vanilla extract
3/4 cup Balance trans-fat-free soft tub margarine spread, chilled
1 cup low-sugar blueberry preserves
1/2 cup spinach puree 

Preheat oven to 375°. Coat an 8" x 8" baking pan with cooking spray. In a large bowl, combine oats, flour, sugar, cinnamon, baking powder, salt and vanilla and stir to mix well.  Add the margarine and cut it quickly into dry ingredients with two knives until the mixture resembles coarse meal and is no longer powdery. Do not overmix, bits of margarine will still be visible. Set aside about half of the oat mixture; press the rest firmly into the pan. Bake until lightly browned at the edges (but not fully baked), 13 to 15 minutes.  Meanwhile, mix the preserves with the spinach puree in a small bowl. Spread blueberry mixture over the partially baked oat layer, then sprinkle with reserved oat mixture. Bake until topping is slightly browned, 20 to 25 minutes. Set the pan on a rack to cool completely before cutting into 12 bars. * Recipe from Deceptively Delicious by Jessica Seinfeld.