Welcome to Bon Appétit Bake Club , a community of curious bakers. Each month senior Test Kitchen editors Jesse Szewczyk and Shilpa Uskokovic share a must-make recipe and dive deep on why it works. Come bake and learn with us—and don’t forget to join the Bake Club Group chat over on Substack . A whole lemon—pith, skin, flesh, and all—is a powerful thing. When used correctly, that power can be harnessed for good, heightening the citrus fruit’s bright, piercing notes to soaring new heights. Here, classic lemon bars call upon the brute strength of two whole lemons to embolden the custard with a Lemonhead-like flavor. The lemons are chopped up and blended into pulpy submission along with added juice. (Organic lemons are ideal here, but a good scrubbing of conventional ones will also work.) Blending extracts all of the precious oils from the peels, imbuing the juice with another dimension of lemon flavor. It’s sweet, sour, a touch bitter, and delightfully puckery.…