Since I love lemon, you might think that I love lemon bars. Unfortunately, this is not true. More often than not, lemon bars are just plain awful. The lemon filling is usually either gummy or too gelatinous and the base is almost always bland, soggy or both. The lemon flavor is rarely as clear as it could be and, while lemon bars shouldn't be as tart as the filling for a lemon meringue pie, where the meringue acts to temper the semi-tart lemon flavor of the filling, it should still be bright enough that one bite sends the "this is lemon" message to your brain. In short, I usually pass on lemon bars.
Of course, if I make the bars myself, I have no problems eating them. This recipe seems to solve all the lemon bar problems that I just listed, turning out bars that are as close to perfect as I can recall having.
The base is a light and tender shortbread cookie, which crumbles gently into your mouth and retains some crispness in spite of the moist topping. The topping is just thick enough to hold together well and has a bright, but not overly tart, lemon flavor. In fact, the flavor is tempered by the addition of some sour cream, which gives the bar a great mouthfeel.
I used my Baker's Edge pan to ensure even baking. Don't have one yet? No worries - just use a 9"x13" baking pan and plan to take a couple of minutes off the final baking time.
I topped these off with a sprinkling of powdered sugar, but that is entirely optional. The whole batch will be gone in a flash - with or without the extra sprinkle.

Sour Cream Lemon Shortbread Bars
Crust
1 1/2 cups all-purpose flour
1/3 cup sugar
2 tsp lemon zest
1/4 tsp salt
3/4 cup butter, chilled and cut into several pieces

Lemon Topping
3 large eggs, room temperature
1 1/2 cups sugar
6 tbsp sour cream
3 tbsp all purpose flour
1/2 tsp baking powder
1/2 tsp salt
1/4 cup lemon juice
Zest of 2 lemons (1 generous tbsp)

Preheat oven to 350F.
In the bowl of a food processor, whizz together the flour, sugar lemon zest and sald. Add in butter and pulse until mixture reaches a crumbly, sandy (with some pea-sized chunks of butter remaining) pieces. Press evenly into the Baker's Edge pan (or 9"x13" pan) bake for 16-19 minutes, until just slightly golden at the corners.

While the crust is baking, beat together the remaining ingredients until smooth. When the crust comes out of the oven, pour in the lemon filling while it is hot, then return pan to the oven.
Bake for 25 minutes, until set and slightly browned at the corners.
Set pan on a wire rack to cool completely.
Makes 16 large bars.