| Source: | Joanne Chang |
|---|---|
| Yields: | 16 1 1/2" bars |
| Prep Time: | 1 hour |
| Cook Time: | 1 hour |
| Total Time: | 5 hours |
In a large bowl, cream together the butter and both sugars until light and fluffy, about 5 minutes. Beat in vanilla untill thoroughly combined.
In a medium bowl, sift together both flours, the baking powder, and the salt. Slowly blend the dry into ingredient into the wet ingredients, scraping down the side of the bowl until completely blended.
Scrape the dough from the bowl onto a sheet of plastic. Wrap well and press down to form a 1/2" thick square. Refrigerate the dough until it's firm but stll pliable, about 20 minutes. Heat oven to 350. Prepare 2 sheets of parchment paper, each 11x11".
Note: To save time, I started on the curd while the shortbread dough was in the refrigerator.
When dough is firm, unwrap it and put it between the parchment paper. Roll the dough to an approximate sqaure, slightly larger than 8x8" and about 1/4 inch thick. Remove top sheet of parchment paper, trim dough with a dull knife to an 8x8" square, and put into 8x8" baking pan. Press dough into into the bottom of the pan, letting the excess parchment paper come up the side (trim it about an inch above the rim). The dough should be an even thickness but doesn't need to be perfectly smooth. Bake until the shortbread is light golden on top, 25 to 30 minutes.
Remove the pan from the oven, but keep the heat set to 350 as you make the lemon curd.
In a medium saucepan, heat the lemon juice, butter, and cream to just under a boil; the butter should be melted. Remove from the heat.
In a medium bowl, whisk together by hand the sugar, eggs, and yolks until combined. Whisk in a bit of the hot liquid and then gradually whisk in a little more until it's all added. This technique, called tempering, heats the eggs slowly and gently so they don't curdle.
Pour the mixture back into the saucepan and heat on medium, stirring constantly with a wooden spoon, scraping the sides and bottom of the pan to keep the eggs from scrambling. Cook until the lemon curd coats the spoon thickly enought ot leave a line when you draw your finger through, 5 to 8 minutes.
Note: I found the curd thickened very quickly once it began to thicken, so be careful about leaving it alone.
Remove from the heat and strain through a fine sieve. Stir in the salt and vanilla.
Pour curd over baked shortbread and smooth it evenly with a spatula, if needed. Bake until the curd has set and jiggles like firm jello, 15 to 20 minutes. Let cool to room temperature, then gently tug the parchment on all sides to loosen the bars from the pan. Lift them out and onto a cutting board and refrigerate until the curd has completely set, at least 4 hours. Trim the sides for a cleaner look and cut into 16 pieces.