Tangy custard is like a spoonful of sunshine . . .
Don’t take the name literally – lemon curd isn’t supposed to be curdled. The chances of it curdling, however, are good. Or rather, bad?
Curd is basically a lemon custard. Egg whites start setting at 144F (62C) and yolks at 149F (65C), but for the sake of food safety, eggs should be cooked to 160F (71C). So it’s very easy to end up with cooked, curdled eggy bits in lemon curd.
Let’s not think about that. Let’s focus on the perfect curd instead: satiny, nicely balanced between tart and sweet, and firm enough to spread or dollop. So luscious!
To get there, cooks take a variety of routes. Should one use whole eggs or only the yolks? Should the curd be stirred or whisked or power-beaten? Should it be strained? Should one stick to tradition or try new tricks?
In pursuit of perfection, I experimented with five different cooking methods. One was a tricky, no-strain technique that started with creaming butter and sugar with an electric mixer. Another was a backwards recipe that began with melted butter (usually butter chunks are stirred in at the end) and ended with cooking over direct heat rather than in a double boiler. Yet another was a no-waste version that utilized whole eggs.
In the end, I couldn’t improve on my good old “one is the magic number” formula: For every 1 egg yolk, you need 1 tbsp (15 mL) each of sugar, lemon juice and butter. Plus you use 1 tbsp (15 mL) of zest and 1 pinch of salt in the mixture.
In comparison to many recipes, my version is light on the sugar and butter, yet the consistency is just right. It’s even firm enough to double as pie filling without the use of thickeners such as cornstarch or gelatin. As for flavour, there is no hint of that lemon floor polish aftertaste that mars some unfortunate concoctions.
I do admit it is very tangy. But too tangy? It’s relative. Remember, lemon curd doesn’t stand alone. It is spread on scones. It is layered in parfaits and trifles. It fills cakes and tarts, and tops pavlovas. I found a great many recipes that called for twice as much sugar as I normally use. One such test recipe was sickeningly sweet. Not only that, the more sugar you add, the looser the curd, so the more butter you require. It’s a slippery slope.
- Use freshly squeezed lemon juice only. This is non-negotiable. Bottled juices have additives with a bad aftertaste.
- Zest-haters, take note: You should never omit it. The zest (shiny yellow part of the rind) contains the lemon’s essential oils; you need it to maximize flavour. (The lemon’s juice mainly contributes tang.) I don’t want the zest to mar the silky texture of my curd, however, so I strain it out. This extra step is worthwhile.
- To decrease the incidence of curdled curd, use a double boiler or heatproof bowl set over simmering water — not direct heat.
- How you stir affects the result. If you stir with a spatula, curdled bits (especially stray whites) are inevitable. If you stir (not beat!) with a whisk, the custard is less like to curdle. If you whisk vigorously, curdling is even less likely, but the curd will develop a foamy layer. If you use an electric beater, the mixture shouldn’t curdle or require straining, but the texture will be fluffy or mousse-like, rather than glassy.
- Don’t worry if your warm curd seems a bit loose. It will thicken and set as it cools.
- Most recipes advise you to cover the surface of the finished curd with plastic wrap before storing it. Do so if you wish, but in my experience, these custards never develop a skin. I simply spoon lemon curd into a storage tub and pop on the lid.
- My curd keeps in the fridge for up to a week. And surprise – you can successfully freeze lemon curd.
Playing With Lemon Curd
- Slather curd between the layers of a cake. It does tend to soak into cake, so you may wish to spread a thin layer of protective icing over the cake before adding the curd.
- Fill sandwich cookies with curd.
- Swirl curd into uncooked cheesecake for a marbled effect. Or simply spread curd over vanilla cheesecake.
- Make lemon tarts. Fill cooked tart shells with curd. Or add curd to raw shells and bake for about 20 minutes at 325F (160C). Top with whipped cream and fruit.
- Make lemon cream sauce. Beat 1 cup (250 mL) of heavy cream to soft peaks. Beat in 1 cup (250 mL) of cold, firm curd. Pour it over fruit or angel cake or other desserts. Or freeze it to make lemon “ice cream.”
- Make a parfait, alternating layers of vanilla ice cream and curd. Decorate the top with berries.
- Use your lemon curd recipe to make lime, orange or grapefruit curd.