Created by KittenCal on June 7, 2012
Step 1: In a heavy-bottomed saucepan whisk together lemon juice, zest, sugar and eggs. Stir in butter and cook over medium-low heat whisking vigorously and continuously until the curd is thick enough to hold a ripple mark when the whisk is lifted from the curd and the first bubbles appear on the surface (this should take about 6-7 minutes).
Step 2: Transfer to a bowl then cover the curd using plastic wrap spread directly over the curd. Chill for a minimum of 2 hours before using or up to 1 week.