Recipe from America’s Test Kitchen which states, “For bright citrus flavor, successful lemon bars depend on ample amounts of fresh lemon juice, yes, but also a generous amount of lemon zest, which provides round, floral notes. We used four lemons for our lemon curd filling, which yielded a whopping 2/3 cup of juice and 1/4 cup of zest. The other major ingredient for lemon curd is eggs, and lots of them. Two whole eggs and seven yolks gave us a luxurious curd with good thickening properties. To tame the curd’s pucker power and make it ultracreamy, we added a small…