Instructions

1. Preheat your oven to 375 degrees F.
2. Grease a 9×13 inch pan.
3. In a medium bowl, stir together 1 cup of sugar, 3 cups of flour, and baking powder.  Mix in the salt and lemon zest, then use a fork or pastry cutter to blend in the butter and egg.  {The dough will be crumbly.}
4. Pat half of the dough into the prepared pan.
5. In another bowl, stir together the sugar, cornstarch, and lemon juice, then gently mix in the blueberries.
6. Sprinkle the blueberry mixture evenly over the crust then crumble the remaining dough over the berry layer.
7. Bake for 45 minutes, or until the top is slightly brown.
8. Cool the bars completely before cutting into squares.