In a small saucepan, whisk together egg yolk and egg until combined. While whisking, pour in sugar, lemon juice, and zest, and continue whisking until creamy and well incorporated, about one minute. Place over medium heat, whisking constantly, until the custard thickens and can coat the back of a wooden spoon, about 8-10 minutes.
Remove the pan from the heat, and stir in the butter, one cube at a time. Strain into a bowl or jar, cover the surface with plastic wrap, and chill in the refrigerator for at least one hour. Keep refrigerated.
Adapted from David Lebovitz‘s Improved Lemon Curd and Martha Stewart’s Lemon Curd, The Martha Stewart Living Cookbook (MSL Omnimedia, 2000).
This makes a delicious homemade gift. Just be sure to let your recipient know to keep it refrigerated.
Make it Dairy-Free
Reader Naomi L. made this lemon curd dairy-free by substituting the butter with one egg yolk plus 2 tablespoons of olive oil.
Can Lemon Curd Be Canned?
Many people ask if lemon curd can be processed in a hot water bath for long-term storage, similar to jams and jellies. I know friends who do make and can fruit curds. In general, what I have learned is frozen lemon curd can be kept much longer (up to 1 year) than lemon curd that is preserved by canning (3-4 months), but the key in doing it the latter way is using bottled versus fresh lemon juice. The worry is that fresh lemon juice lacks the acidity to make the canning safe.I recommend checking out these two links that have info/recipes for canning lemon curd:http://www.uga.edu/nchfp/how/can_02/lemon_curd.html http://www.uga.edu/nchfp/publications/nchfp/factsheet