Blackberry Shortbread Bars

These bars are a study in contrasting textures:  a custardy filling with a streak of fresh blackberries atop a dense shortbread crust and a buttery crumble topping.  These bars have an excellent shelf life, so pack them in cello bags, tie with a bow, and you've got Valentine's Day gifts for the special people in your life.   Or serve warmed at home with vanilla ice cream or fresh whipped cream.

Blackberry Shortbread Bars


Ingredients

Crust

3            cups           unbleached A.P. flour
1 1/2      cups           sugar
1/4         tsp              salt
1 1/2      cups            butter, cubed and chilled


Filling

4                                eggs
2             cups            sugar
1             cup              sour cream
3/4          cup              unbleached A.P. flour
1/8          tsp                salt
                                    zest of 1 small lemon
6             cups              blackberries

Procedure

1. Preheat oven to 325° convection (350° conventional) and place rack in the middle of the oven.
2. Generously butter a 9 x 13" baking pan.  We used a Dansk enamel pan this time, but we have also used pyrex with good results.
3. In food processor, combine dry crust ingredients well.  Add butter and process until mixture is crumbly and butter is well-distributed.
4. Reserve about 2 cups of mixture, then spread the rest in the bottom of the baking pan.  Press well to create an even layer, then bake until golden brown, 20 minutes in our oven.  Remove and cool 15 minutes.
5. Combine all filling ingredients except the blackberries, and mix well.  Add blackberries.
6. Spread filling evenly over pre-baked crust.  Sprinkle reserved crust mixture on top of filling.
7. Bake until bars have puffed up and feel firm through to the center, and top is golden brown, around 1 hour in our oven.
8. Remove to cooling rack and cool well before cutting into bars.