Inspired by a recipe from Melissa McKinney, perhaps the most valuable lesson I learned is that grating the dough rather than rolling it out makes for a lighter, fluffier, and chewier bar.
For the lemon curd:
For the short bread bars:
For the lemon curd:
Crack the eggs into a large bowl and set aside. Combine the rest of the ingredients in a medium pot and whisk over a medium-high heat until the butter has melted and the mixture is nearly boiling.
Remove the pot from the heat and while whisking the eggs as vigorously as you can, add dribbles of the hot mixture in the smallest amounts until the eggs are fully incorporated. Pour the entire mixture back into the pot and set over a medium-high heat. Simmer and constantly whisk until the mixture thickens and the whisk, when dragged over the curd’s surface, leaves whisk marks.
Pour the curd into a bowl and cover the curd’s surface with a layer of Saran Wrap. The curd will keep in the fridge for 3-4 days.
For the shortbread bars:
Add the flour, baking powder and salt to a bowl. Whisk to incorporate and then whisk in the ground almond and sugar mixture.
Using a mixer, beat the sugar and butter at medium until creamy. Turn the mixer to low and add the eggs and vanilla. Once incorporated, add the flour mixture. When the dough is well mixed, split the mixture in half and wrap each half in Saran wrap. Chill in the refrigerator for about 2 hours or up to 2 or 3 days.
Preheat the oven to 350 degrees.
Line a square cake pan with parchment paper. Using the largest setting of a box grater, grate the first ball of dough into the bottom of the pan. Gently spread the dough bits around and into the corners until there is an even layer. Gently smooth a healthy layer of lemon curd over the dough using an offset spatula if you have one. Grate the second ball of dough overtop. Cook for 30-35 minutes until the top is golden brown. Remove from the oven and let cool completely. Remove the shortbread from the pan and cut into squares. Dust with powdered sugar and serve.