Lemon Raspberry Cake
Updated: Sep 13, 2019
I know you’ve heard me say this a thousand times, but lemon is the best. I realized that I have a favorite lemon-based cake, and that it must be shared with the world! I recently had a request to make a lemon cake with raspberry filling, and it was the perfect combination for those who love sweet, tart, and fruity.
The lemon cake itself has a triple blast of lemon, with lemon juice, lemon zest, and lemon extract all included. It’s just dense enough to stay moist with lots of butter and sour cream, but then lightened to fluffy nirvana by whipped egg whites. Paired with the silkiest lemon swiss buttercream and a tart and not-too-sweet fresh raspberry curd, it’s a great celebration or birthday cake, especially for the summertime.
MAKES one 8” 3-layer cake
If you are going to use the raspberry curd, it must be made at least 2 hours in advance of putting the cake together so it has time to chill.
If you are going to use lemon curd in the buttercream frosting, that also must be made at least 2 hours in advance - same reason. I prefer the punch of a natural and strong lemon flavor, and you can’t really get that through using extract only. You don’t have to, though, and can always just use more lemon extract to make it lemon-flavored.
You could also skip the raspberry curd and make this a triple lemon cake, filling it with lemon curd. Find instructions for that plan below in the frosting section.
If you want to skip the curd entirely and just make a lemon cake with lemon buttercream filling & frosting, make 1.5 times the frosting recipe below to make sure you have enough to fill, frost, and decorate your cake.
3 cups (12-13oz) fresh raspberries, washed OR frozen raspberries (frozen are just as good in this recipe, I promise!)
150g sugar (3/4 cup) (you can increase this up to 1 cup total for a sweeter curd, or reduce to 1/2 cup for more tartness)
2 Tablespoons lemon juice
2 Tablespoons water (only include this if your raspberries are fresh not frozen)
2 egg yolks (save the whites for your buttercream!)
2 Tablespoons cornstarch
1/8 teaspoon kosher salt
1 Tablespoon chilled butter, diced into small pieces
Food processor/blender, or an immersion blender and a medium bowl
Small bowl & small whisk
Glass bowl/container for storage
In your medium saucepan, combine 3c raspberries, 100g sugar (1/2c), 2TB lemon juice and 2TB water and boil over medium-high heat.
Once boiling, reduce heat and simmer for 5 minutes.
Remove from heat and let stand 5-10 minutes.
Process until smooth in a food processor, blender, or in a separate bowl using an immersion blender (if using the immersion blender I recommend letting it cool for slightly longer). Rinse out your saucepan.
Strain the mixture using a fine mesh sieve back into the saucepan. Clean your sieve (you’ll be using it again).
In a small bowl whisk together 2 egg yolks & 2TB cornstarch until smooth - it will be thick!
Whisk the yolk/cornstarch mixture into the raspberry mixture until thoroughly combined.
Boil over medium-low heat, then cook for about 1 minute until large volcano-like bubbles start to pop and the mixture is thick.
Remove from heat, then strain through a fine mesh sieve into your storage container.
Add 1/8tsp kosher salt and 1TB chilled butter pieces, stirring until smooth.
Place a piece of plastic wrap directly onto the surface of the curd, then chill for at least 2 hours before using (or up to 1 week).
I haven’t tried freezing this for use much later, but it works well with lemon curd so it would probably work well here too!
LEMON CAKE LAYERS
1.5 sticks unsalted butter, room temperature/softened (170g)
400g sugar (2 cups), separated in half
6 eggs, separated
270g All-Purpose flour (2.25 cups)
3/4 teaspoon baking soda
1/2 teaspoon kosher salt
2 Tablespoons fresh lemon juice (1 lemon)
2 Tablespoons lemon zest (1 lemon)
1 teaspoon vanilla extract
1/2 teaspoon lemon extract
180g Sour Cream (3/4 cup)
Three 8” round cake pans
CAKE GOOP! and a silicone brush (or shortening to grease & flour to coat)
Stand mixer with two separate bowls, and beater and whisk attachments
Kitchen scale or measuring spoons/cups
Mixing or measuring bowl
Heat your oven to 350° F and goop-up your cake pans (or grease them with shortening and coat with flour, tapping out the excess)
In your stand mixer with your beater attachment, cream together 1.5 sticks butter and 200g (1c) sugar on medium-high for about 5 minutes. Scrape down the sides/bottom of the bowl halfway through.
In a separate bowl, gently whisk together 270g AP Flour (2.25c), 3/4tsp baking soda, and 1/2tsp kosher salt.
With the mixer on medium-low, add 6 egg yolks one at a time, mixing thoroughly between each addition. Scrape the sides/bottom of the bowl as needed.
Add 2TB lemon juice, 2TB lemon zest, 1tsp vanilla, and 1/2tsp lemon extract - mix on medium and then high until fully incorporated, about 30 seconds.
Add your dry ingredients, mixing on low, then medium just until there are no streaks of flour left - don’t overmix. Remove the bowl from the mixer and give a final scrape/stir with your spatula.
Add 6 egg whites and 200g (1c) sugar to your second mixer bowl. Using the whisk attachment, beat on medium, then high, until stiff peaks form.
In three additions, gently fold the beaten egg whites into your batter, taking care to incorporate them completely but gently so that you don't deflate the batter.
Distribute your batter evenly between the prepared cake pans - if you’re using a kitchen scale it should be about 425g of batter in each pan.
Bake for 20-25 minutes, when the edges are pulling away from the sides, the middle of the cake springs back when you gentle press your finger on it, and/or a tester comes out clean. Make sure you don’t over bake! Start checking the layers at 18 minutes if you’re less sure of how to determine when a cake is done and read more about how to tell.
Cool the cake pans on racks for 10-20 minutes, then remove from pans and cool completely.
For easier leveling of your cake layers (see “Put it all Together” below), once they are cooled to room temperature place them in the freezer for 30 minutes up to a few hours. If you’d like to put the cake together the next day or at a later date, you should freeze the cake layers until they can be handled without bending, then wrap them each in two layers of plastic wrap and then two layers of aluminum foil. They’ll keep in the freezer for months!
LEMON SWISS BUTTERCREAM FROSTING
7 large egg whites (about 245g - each egg white is ~35g)
1 and 2/3 cup sugar (310g)
pinch of salt
Optional: 1/4 teaspoon cream of tartar
4 sticks unsalted butter, cut into tablespoons, room temperature*
1/2-1 cup lemon curd** (recipe here, must be made 2 hours in advance)
1/2 teaspoon lemon extract
Optional: yellow gel food coloring
stand mixer with whisk attachment
small saucepan that will allow your mixer bowl to sit inside, but not touch the bottom
*If you’re making this last minute and your butter is cold, check out tip #7 here for quick room temperature butter. It’s really important that your butter isn’t cold, and also isn’t melty. **If you want to fill the cake with lemon curd instead of raspberry curd, make 2.5 times the amount of lemon curd - meaning 10oz each lemon juice, egg yolk, and sugar. That should give you enough to fill each of the layers with 1 cup of lemon curd, and then have enough to use for the frosting.
Place about an inch of water in your saucepan and bring it to a boil. Once boiling, lower heat to a simmer.
Add 245g egg whites (5), 310g sugar (1.66c), a pinch of salt, and the optional 1/4 tsp cream of tartar to your stand mixer bowl, and hand whisk to combine.
Place the stand mixer bowl on the saucepan, so you’re creating a double boiler. Whisk vigorously by hand every two minutes or so, until the liquid reaches 165F on your candy thermometer, about 10-12 minutes.
Immediately place the bowl onto the stand mixer, and whisk on high until the mixture has turned glossy, and is not warm at all. This usually takes around 10-12 minutes. If you touch the outside of the bowl and it’s no longer warm, you can test the mixture with a clean fingertip to be sure. If you move on to the next step and it’s not fully cooled, you will not end up with frosting - you’ll end up with a soupy mess!
Once cool, reduce the speed to medium and begin to add your tablespoons of butter individually, with about 3-5 seconds in between each.
Once your mixture finally looks like frosting, add 1/2 cup of lemon curd and 1/2 teaspoon lemon extract, and mix to combine. Taste, and add more to your liking. Then add a few drops of yellow food coloring.
Use immediately or within a few hours. Can be refrigerated up to two weeks, and frozen up to a year or more. If you’re going to use it after chilling, let it come to room temperature completely before re-mixing to use.
PUT IT ALL TOGETHER!
Cake board or carrier base
Piping bags/tips and decorations as desired
Level each layer with a serrated knife to remove any domed top as needed.
Place your cake board on top of your turn table.
Spread about a teaspoon of frosting in three triangular dollops on the center of your board or plate, then place your first cake layer centered on top. Press down gently to make it stick with the frosting as glue.
Fill half a piping bag with a 1/2” round tip with lemon buttercream, and pipe a ring around the edge on top of your first layer. This will serve as a barrier so your curd will not ooze out of the sides as you stack additional cake layers on top.
Stir your curd thoroughly to make it smooth before spreading half of it (about 1 cup) on the cake layer, within the buttercream border.
Center and place your next cake layer on top, then repeat steps 3 & 4.
Place your final cake layer on top, then place in the fridge for 15 minutes.
Re-whip your buttercream for 20 seconds in your mixer to aerate, then crumb coat the cake and return to the fridge to chill for 20 minutes. Don’t know what crumb coat means? Check it out!
Re-whip your buttercream once more, then coat the whole cake with a thick layer of frosting, and decorate as desired!
The cake will keep up to 48 hours in *cool* room temperature conditions, up to 5 days in a covered container in the fridge, or up to 6 months in a box/container in the freezer that is well-wrapped with two layers of plastic wrap and two layers of aluminum foil.
Adapted from Sweetapolita and Tutti Dolci