This lemon curd cake is UNBELIEVABLY moist and bursting with all natural lemon flavor. This cake features a homemade lemon curd that gets its beautiful color and richness from egg yolks while the lemon cake batter is made with egg whites - so you won't have any leftover separated eggs! This poke cake is topped with a fluffy lemon cream cheese frosting to really drive home the lemony goodness.
how to make homemade lemon curd
Homemade lemon curd is surprisingly easy to make and is so much more bright, fresh, and flavorful than store-bought! If you've never heard of it, lemon curd is very similar to a custard in texture and consistency, but generally does not contain milk or cornstarch. Instead, it gets it's thickness, richness, and structure from egg yolks and butter. And (obviously) it's bursting with lemon flavor!
To make this lemon curd, all you need is lemon zest + juice, sugar, egg yolks, salt, and butter. The process involves 4 main steps:
- Whisk: Combine the lemon zest and juice, sugar, egg yolks, and salt in a pot. Whisk well to combine.
- Cook: Place the pot onto a stove-burner set to medium heat. Cook, whisking constantly, until the mixture boils. Reduce heat to maintain a gentle simmer, and continue cooking while stirring constantly until the curd thickens enough to coat the back of a spoon.
- Add butter: While the curd is still hot, whisk in the butter until melted, smooth, and creamy.
- Cool: The butter helps cool the curd down slightly, but it still needs some time in the fridge to allow the butter to firm back up and set the curd into thick, liquid gold!
leftover egg whites from the curd
Since the lemon curd needs 4 egg yolks to make, I really wanted to have the cake use up the leftover egg whites. Because if you know me, you know that I'm going to set aside the egg whites in my fridge and completely forget to use them.
I also feel like the egg whites make the cake even better than a cake made with whole eggs! The whites make the cake lighter and airier (without the extra weight from egg yolks) which makes it extra tender and moist! They're also great because the lower richness level really allows the lemon flavor the shine.
Plus, you'll have a whiter finish to your cake, which will make the yellow curd filling POP.
how to make lemon curd cake
For the sake of keeping things extra easy in this recipe, we're using the reverse creaming method for this cake! Not only is it easier, but it yields a distinctly moist and tender yet dense crumb - think: vanilla birthday cake you'd get from a bakery! Cake batter made with the reverse creaming method is also less prone to overmixing and is just all around more fail-proof!
To make the lemon cake:
1. Whisk together dry ingredients then cut butter in. You're looking to get the mixture as fine and crumbly as you can, with teeny tiny butter pieces.
2. In a separate bowl, whisk together wet ingredients.
3. Whisk wet ingredients into flour / butter mixture. Once the dry ingredients disappear into a streak free batter, give it a few extra whisks to really smoothen out the batter - a few clumps are fine though!
4. Pour into your baking pan and bake!
5. Cool for 10 minutes in the pan, then turn onto a wire rack. Set aside to cool completely to room temperature before filling and frosting.
how to make lemon cream cheese frosting
1. Cream together butter and cream cheese until smooth.
2. Add remaining ingredients and whip until smooth and fluffy! Super simple!
Tip: If you find your frosting is too stiff, you can thin it out with 1 to 2 tablespoons of lemon juice or milk. If the frosting is too soft, you can add more powdered sugar, but I personally find that makes it overly sweet. I prefer to pop the frosting into the fridge for 20 to 30 minutes or until firm enough to use.
1. Poke holes into the cooled cake. Using a straw, cake pop stick, or similarly sized utensil, poke holes all across the surface of the cake. You should leave a little over ¼ inch distance between each hole and don't allow the stick to pierce more than about ⅔ of the way through the cake (otherwise the filling will seep through the bottom).
2. Transfer the cooled curd to a piping bag, and use it to fill the holes in the cake. You can also just spread the curd over the top of the cake and let it seep into the holes, but I find a piping bag helps with better control. Save a bit of curd for swirling on top!
3. Frost and top with more lemon curd! Start by spreading the cream cheese frosting over the filled cake. Dollop some of the remaining curd over the frosting and use a spatula or spoon to lightly swirl it into the frosting.
4. Slice and dig in!
tips for lemon curd success
Lemon curd is very easy to make, but there are a few key details to keep in mind to ensure lemon curd success!
- Fresh lemon zest and juice: It's the main flavor profile of the curd, so using freshly zested and squeezed lemons makes all the difference! This is also true for the lemon cake and frosting.
- Medium heat: The temptation to speed up the process by using high heat is very much huge, but it's a big no-no when making lemon curd! Using high heat makes it more difficult to control and runs the risk of burning the bottom of the curd and / or curdling the mixture. Most lemon curds are made using a double broiler, but stove-top works just as well as long as it's on a lower heat setting.
- Whisk CONSTANTLY! Another key to a smooth and velvety lemon curd. Whisking allows the curd to cook evenly and helps keep the bottom from scorching.
- Whisk the butter as soon as you add it to the hot curd: This helps emulsify it and prevents breakage / curdling. If you leave the butter to melt too long before mixing, it's more likely to separate as it cools.
- Cover with plastic wrap pressed against the surface of the curd: This helps prevent skin formation on top!
- Cool completely: Unless a recipe says otherwise, warm lemon curd is typically too soft and runny to use for anything. It's best to refrigerate curd until it's thick and creamy!
Keep your filled and frosted cake stored in the fridge and covered with plastic wrap or an inverted bowl / cake cover. This cake will keep for around 4 to 5 days in the fridge.
The cake, filling, and frosting will firm up slightly after sitting in the fridge. If you prefer a softer slice, let the cake sit out at room temperature for about 30 minutes before serving.
check out these other recipes!
Lemon Curd Cake Recipe
For the lemon curd:
- 1 tablespoon fresh lemon zest (about 1 large lemon worth)
- ⅓ cup (80mL) freshly squeezed lemon juice (about 2 lemons)
- ¾ cup (150g) granulated sugar
- 4 large egg yolks (save the whites for the cake!)
- ¼ teaspoon salt
- ½ cup (1 stick / 115g) cold unsalted butter, cut into cubes
For the lemon cake:
- 1 & ½ cups (180g) all-purpose flour, spoon and leveled
- 2 tablespoons cornstarch
- ¾ cup (150g) granulated sugar
- 1 teaspoon baking powder
- ¼ teaspoon baking soda
- ½ teaspoon salt
- 5 tablespoons (75g) unsalted butter, softened to room temperature
- 4 large eggs whites, at room temperature
- ½ cup (120g) sour cream, at room temperature
- 2 tablespoons vegetable oil, or any neutral flavored oil
- 2 tablespoons fresh lemon zest (about 2 lemons worth)
- 2 tablespoons freshly squeezed lemon juice (about ½ a lemon)
- 1 teaspoon pure vanilla extract
For the lemon cream cheese frosting:
- 12 tablespoons (175g) unsalted butter, softened to room temperature
- 6 ounces (170g) block cream cheese, at room temperature
- 2 & ½ cups (325g) powdered sugar, sifted
- 1 tablespoon lemon zest (about 1 lemon worth)
Make the homemade lemon curd:
- In a medium sized saucepot, combine lemon zest and juice, sugar, egg yolks, and salt. Whisk to combine.1 tablespoon fresh lemon zest, ⅓ cup (80mL) freshly squeezed lemon juice, ¾ cup (150g) granulated sugar, 4 large egg yolks, ¼ teaspoon salt
- Place your pot onto a stove-burner set to medium heat. Cook, whisking constantly, until the mixture boils.
- Reduce heat slightly to maintain a gentle simmer, and continue cooking the curd (still whisking constantly) until it thickens enough to coat the back of a spoon. This will take about 10 minutes from start to finish.
- Take the thickened mixture off the heat and add in your cold butter. Whisk until the butter is melted and combined into a smooth mixture.½ cup (1 stick / 115g) cold unsalted butter,
- Pour the lemon curd into a medium bowl. Cover with plastic wrap pressed against the surface of the curd (to prevent a skin from forming) and refrigerate for 2 hours, or until fully cooled and thickened to the consistency of pudding.
Make the lemon cake:
- Preheat your oven to 350°F. Butter an 8x8 inch pan and line the bottom and sides with parchment paper. Set aside.
- In a large bowl, whisk together flour, cornstarch, sugar, baking powder, baking soda, and salt to combine.1 & ½ cups (180g) all-purpose flour,, 2 tablespoons cornstarch, ¾ cup (150g) granulated sugar, 1 teaspoon baking powder, ¼ teaspoon baking soda, ½ teaspoon salt
- Cut butter into the dry ingredients using a fork or your fingers. Try to break up the butter pieces as best you can. You should be left with a very fine, dry, and crumbly mixture.5 tablespoons (75g) unsalted butter,
- In a separate medium bowl, whisk together egg whites, sour cream, oil, lemon zest and juice, and vanilla to combine.4 large eggs whites,, ½ cup (120g) sour cream,, 2 tablespoons vegetable oil,, 2 tablespoons fresh lemon zest, 2 tablespoons freshly squeezed lemon juice, 1 teaspoon pure vanilla extract
- Pour the egg mixture over your butter / flour mix. Whisk together until you no longer see any dry streaks of flour. Once combined, give the mixture an additional 20 seconds or so of vigorous whisking to make sure it's all whipped up nicely. There may be a few tiny clumps in the batter - that's totally fine!
- Pour the cake batter into your prepared baking pan and spread into an even layer. Bake in the center of your preheated oven for 30 to 35 minutes, or until lightly golden brown along the edges and a skewer inserted into the center comes out with a few moist crumbs but no wet batter.
- Cool the cake for 10 minutes in the pan, then turn onto a wire rack. Set aside to cool completely to room temperature.
Make the lemon cream cheese frosting:
- In a large bowl, combine butter and cream cheese. Using an electric mixer fitted with the paddle attachment, beat together on medium speed for about 1 to 2 minutes or until combined and smooth. You can also do this by hand with a wooden spoon, but it's a bit of a workout!12 tablespoons (175g) unsalted butter,, 6 ounces (170g) block cream cheese,
- Add powdered sugar and lemon zest. Mix together on low speed until the sugar is dissolved, then increase the speed to high and whip until smooth and fluffy.2 & ½ cups (325g) powdered sugar,, 1 tablespoon lemon zest
- If your frosting is too thick, you can thin it out with 1 to 2 tablespoons of lemon juice or milk. If the frosting is too soft, pop it into the fridge for 20 to 30 minutes or until firm enough to spread.
Filling and assembling the cake!
- Use a straw or cake pop stick to poke holes all along the top of the cake, going no more than about ⅔ of the way down. Take care not to poke through the bottom, otherwise the filling will seep out! Try to space the holes a little over a ¼ inch apart.
- Transfer your cooled lemon curd to a piping bag or plastic bag and snip a small piece off the tip. Use it to pipe the lemon curd into the holes you just poked into the cake. Reserve a bit of lemon curd for swirling into the frosting on top.
- Spread your lemon cream cheese frosting on top of the cake. Dollop some of the reserved lemon curd and use a spoon or spatula to lightly swirl it into the frosting.
- Slice and enjoy! Keep leftovers stored in the fridge until ready to serve.