Lemon Curd

Lemon curd, like many great recipes, is made with only a few key ingredients. How you incorporate those ingredients makes all the difference when it comes to taste and texture.

What Makes a Great Lemon Curd Recipe?

I set out to make a lemon curd that would be tart and sturdy enough to layer between rounds of cake, but also sweet enough to eat on its own, one spoonful at a time, straight from the jar.

How To Make the Best Lemon Curd

A good lemon curd has a glossy finish, holds together like pudding, feels smooth and creamy on the tongue, and has a nice balance of flavor between tart and sweet.

After experimenting with variations of five different lemon curd recipes, I finally settled on my favorite. The result is the recipe below: a version adapted from the recipe I first learned while taking classes at my local culinary school.

The Right Ratio of Eggs to Lemon Juice

I used a ratio of 3 tablespoons of lemon juice per whole egg. This creates a curd with tart lemon flavor, but that's still thick enough to use in other desserts (for instance, between layers of cake).

I found that when I used less juice, the curd was still nice and thick, but it had an eggy flavor to it. When I used more juice per egg, it created a thinner curd that was the consistency of ketchup rather than firm pudding. The flavor was still great, but it wouldn’t work between cake rounds, or hold its shape in tarts (though if you want a curd that you could drizzle over something like ice cream, this would be perfect).

How Much Sugar and Butter to Use in Lemon Curd?

I used just enough sugar to take the sour edge off the lemon, but not so much that this citrus beauty was overshadowed with saccharine flavor. I definitely wanted the lemon to be the star of the show.

I also use a fair amount of butter in this recipe. I like the velvety mouthfeel that butter provides, so I use a lot. If you'd rather use less, play with the amount of butter to suit your liking and taste as you go. If you are happy with less, then by all means, leave a couple of tablespoons out.

When To Add the Butter to Lemon Curd

The point in the recipe when you add butter has a real impact on the texture of the finished lemon curd. Two of the recipes I tested recommended adding butter off the heat once the curd had completely thickened. Both of these versions had a slightly grainy texture that no one really enjoyed.

In the versions where I added the butter while the curd was still on the heat (either all at once or bit by bit), the curd ended up smooth and velvety in texture.

Conclusion: Add the butter on heat while the curd is coming together, not after it has thickened.

Why Strain Your Lemon Curd

It’s best to strain this lemon curd for three reasons:

• If you make curd with whole eggs, you may have noticed white cord-like structures attached to the yolk. These cords are called chalazae, and they hold the yolk in the center of the egg. They don’t break down easily and can leave little eggy bits impacting the texture of the curd. You strain the curd to get those bits out.
• I like adding citrus zest to my curd to increase the lemon flavor, but I don’t love having bits in my finished curd, so I strain it out.
• On the off chance that your curd got a little too hot while you were cooking it, straining will remove any scrambled eggy bits. (Don’t worry, your curd is still fine to eat!)
• Conclusion: Strain your curd!

What To Do If Your Curd Won’t Thicken

Remove the curd from the stove when it’s the consistency of pourable pudding. If it’s thickened but seems more like heavy cream or eggnog, then it needs a little more time. Keep whisking over heat and be patient until it thickens. (Remember: The curd will become thicker once it cools.)

If you’ve cooked the curd well beyond the recommended time and it’s still thin like water, chances are your measurements were off and you added too much juice—or not enough egg.

To thicken it, whisk an egg yolk in a small bowl. Use a ladle to scoop up a small amount of the warm, liquid curd and slowly drizzle it into the egg yolk while whisking constantly. Then pour this mixture back into the pan with the curd. Continue whisking for 5 minutes.

If all else fails and your curd is still not thickening, add a cornstarch slurry. It will impact the color a bit and the texture might be a little grainy, but it will still taste great.

And if it still won’t thicken, then tell everyone you made a fantastic lemon glaze and pour it over vanilla ice cream or slices of cake.

Conclusion: Thick or thin, your curd will still taste incredible.

What To Do if Your Curd Breaks

You shouldn’t see any bubbles from simmering or boiling while cooking your lemon curd. Creamy curds like this one come together over low temps.

If your curd looks lumpy or curdled, remove it from the heat. Transfer it to a bowl and whisk vigorously until it smooths out again. Then, strain it to remove any lumps or any eggy bits. Transfer it back to the pan, lower the heat, and finish the recipe.

If you’re having trouble with temperature, it might be your stove. So try cooking your curd over a double boiler instead. Fill a medium pot with a couple of inches of water and bring it to a simmer. Put a glass or nonreactive metal bowl, over the water, making sure the bottom doesn’t touch the water. Proceed with the recipe, but add an extra five minutes to the cooking time.

Conclusion: Cook your lemon curd low and slow to avoid curdling or lumps.

Ways To Customize This Recipe

Making lemon curd—or any citrus curd—is pretty flexible as long as you keep a few general guidelines in mind.

• For a sweeter or less sweet lemon curd, you can reduce or increase the sugar.
• For a thicker, richer lemon curd, add an extra egg yolk.
• For a richer, more buttery lemon curd, play with the amount of butter.
• For a dairy-free lemon curd, you can even leave the butter out entirely. A dairy-free curd will be really thick, a little gloopy, and have a matte finish rather than a velvety sheen. But it still tastes great, and it is certainly better than going without if you don’t do dairy.
• Great lemon curds can be made with whole eggs, yolks only, or a combination of the two. If you are using yolks only, use two yolks to replace each whole egg.

In addition to lemon, you can make curd with grapefruit, lime, Meyer lemon, passionfruit, and/or orange juice. Simply substitute equal amounts of one juice for another. You can also experiment with using the juice from other fruits, like berries, as long as you add a few tablespoons of lemon juice.

Ways To Use Lemon Curd

As a special after school snack for my children, I fold lemon curd into freshly whipped cream and spoon this on top of raspberries, strawberries, or blueberries. It’s simple to do and takes very little time.

You can also use it to fill a pre-baked tart crust, layer it in between cake rounds, spoon it into yogurt, add it to ice cream, make lemon thumbprint cookies, fill donuts or pastries, or spoon it on top of a pavlova.

You get the idea! The possibilities are limited only by your imagination.

Here are a few ideas:

• Coconut Cake with Lemon Curd and Vanilla Buttercream
• Lemon Meringue Pie
• Lemon Tart
• Triple Layer White Cake with Orange Curd Filling
• Lemon Blueberry Scones

How Long Will Homemade Lemon Curd Keep?

According to the National Center for Home Food Preservation, lemon curd will keep in an air tight container in your fridge for up to four weeks.

Freezing and Preserving Homemade Lemon Curd

The best way to keep it longer than four weeks in the refrigerator is to transfer the curd to freezer containers (leaving about 1/2-inch of room on the top), then freeze it. Thaw the curd in the fridge for 24 hours before you plan to use it. I tasted a batch of frozen (and thawed) curd alongside fresh curd, and I didn’t notice any difference in the texture between the two.

You can also can the curd using the water bath canning method, but the shelf life is only 3 to 4 months. So my feeling is that you might as well freeze it. Also, the acidity in fresh lemons can vary, so the National Center for Home Food Preservation recommends replacing the fresh squeezed lemon juice with bottled juice if you plan to can it (which ensures an acidity level high enough to ward off bacteria).