Step 1

Preheat the oven to 350F.

Step 2

Prepare an 8-inch square glass or ceramic baking dish pan by lightly spraying the inside with baking spray.

Step 3

Make a sling: Cut 2 sheets of parchment paper 15 x 15 inches each. Fold them in half so they are 7 1/2 x 15 inches, which will make them sturdier.

Step 4

Line the pan with the 2 long sheets of parchment paper placed perpendicular to each other in the pan.  This is so you can get the bars out after they are cooked, so don't skip this step. They should be long enough to hang over the sides to use as handles to lift out the baked lemon bars before cutting.

Step 5

Spray the inside of the parchment with baking spray.

Step 6

For the crust: In a food processor combine the flours, brown sugar, cornstarch, lemon zest, baking powder and salt and process until well combined.

Step 7

Add the butter and yogurt to the flour mixture at once and pulse at least a dozen times before turning out into the prepared pan and pressing into an even layer and up the sides of the dish about 1/4-inch so the filling doesn't spill out.

Step 8

Bake until evenly browned about 30 minutes. Shut the oven off and cool the crust on a metal rack for at least 20 minutes.

Step 9

Once cooled, heat the oven to 325°F.

Step 10

Prepare the filling in a medium bowl by whisking together the eggs, honey and lemon zest. Add the flour 1 tablespoon at a time, and the salt and mix well. (this is best to prepare just before baking)

Step 11

Stir in the lemon juice and pour over the cooled crust.

Step 12

Bake until filling is set, about 22 to 25 minutes.

Step 13

Cool completely before lifting the bars out of the pan with the parchment. For best results, refrigerate overnight for a firmer topping.

Step 14

Cut into 12 squares using a clean hot knife, clean in between slices.

Step 15

Dust with confectioners sugar just before serving.